Paper 1 Mock Exam 1

Physics HL

Paper 1 – Mock Exam 1

60 marks

Paper 1A

40 marks

Question 1

It takes an object two seconds to move from point A to point B along the path shown in the diagram.

What is the average speed and the magnitude of the average velocity of the object?

Average speed

Magnitude of average velocity

A. 4 + 2 \pi m s^{-1} 6 m s^{-1}
B. 4 + 2 \pi m s^{-1} 4 + \pi m s^{-1}
C. 4 + \pi m s^{-1} 6 m s^{-1}
D. 4 + \pi m s^{-1} 4 + \pi m s^{-1}
Answer

C.

Video Solution

Done Under 90

Question 2

The diagram shows two masses, M and m that are connected by a string through a pulley, where M > m. The mass of the string and the friction between the string and the pulley are negligible.

What is the acceleration of mass M?

  1. \frac{g(M+m)}{M}
  2. \frac{g(M-m)}{M}
  3. \frac{g(M+m)}{M-m}
  4. \frac{g(M-m)}{M+m}
Answer

D.

Video Solution

Done Under 90

Question 3

A submarine moves through a lake with a speed of 8.0 m s^{-1}. The output power of the submarine’s engine is 2.0 MW. What is the resistive force that acts on the submarine?

  1. 25 kN
  2. 160 kN
  3. 250 kN
  4. 1600 kN
Answer

C.

Video Solution

Done Under 90

Question 4

According to Newton’s third law of motion, what is an action-reaction force pair when a person is sitting on a chair?

Force 1

Force 2

A. The force exerted by the chair on the person The force exerted by the Earth on the person
B. The force exerted by the person on the Earth The force exerted by the Earth on the person
C. The force exerted by the person on the chair The force exerted by the chair on the Earth
D. The force exerted by the person on the Earth The force exerted by the person on the chair
Answer

B.

Video Solution

Done Under 90

Question 5

A constant force F is applied to a rod at point B and as a result, the rod rotates about point A

The length of the rod is 50\; \textup{cm} and the angle between F and the rod is 30^{\circ}. The net torque about point A is 25\; \textup{N\,m}.

What is the magnitude of F?

  1. 25\; \textup{N}
  2. 50\; \textup{N}
  3. 100\; \textup{N}
  4. 200\; \textup{N}
Answer

C.

Video Solution

Done Under 90

Question 6

A stone of mass M is attached to a string and moves in a horizontal circle or radius R. It takes the stone 2 seconds to complete one revolution.

What is the work done by the centripetal force during 1 second of the stone’s motion?

  1. Zero
  2. 2\pi^{2}R^{2}M
  3. \pi^{3}R^{2}M
  4. 2\pi^{3}R^{2}M
Answer

A.

Video Solution

Done Under 90

Question 7

A spaceship travels from Planet X to Planet Y at a speed of 0.9c. The two planets are stationary relative to each other. Observer A on the spaceship measures that the journey takes T hours and Observer B, who is stationary on the surface of Planet X, measures that the distance travelled by the spaceship is L.

What is true about the time the journey takes as measured by Observer B and the distance travelled by the spaceship as measured by Observer A?

\textbf{Time of the journey} \textbf{as measured by Observer B}

\textbf{Distance travelled by the spaceship}

\textbf{as measured by Observer A}

A. Greater than T Greater than L
B. Greater than T Less than L
C. Less than T Greater than L
D. Less than T Less than L
Answer

B.

Video Solution

Done Under 90

Question 8

A block slides down a frictionless ramp from a vertical height of x

The block arrives at the bottom of the ramp at speed v and it eventually comes to rest on a rough horizontal surface after travelling through distance s. The coefficient of dynamic friction between the block and the surface is \mu. What is s?

  1. \frac{x}{\mu}
  2. \frac{\mu}{x}
  3. \frac{v^{2}}{\mu g}
  4. \frac{2v^{2}}{\mu g}
Answer

A.

Video Solution

Done Under 90

Question 9

A solid cylindrical wheel, initially at rest, rolls down a slope without slipping from a vertical height of 3.0\: \textup{m}. The moment of inertia, I, for the wheel is I = \frac{1}{2}mr^{2}, where m is the mass and r is the radius of the wheel.

What is the best estimate for the final linear speed of the wheel?

  1. \sqrt{30} \; \textup{m s}^{-1}
  2. \sqrt{40} \; \textup{m s}^{-1}
  3. \sqrt{60} \; \textup{m s}^{-1}
  4. \sqrt{80} \; \textup{m s}^{-1}
Answer

B.

Video Solution

Done Under 90

Question 10

A thermally isolated tube contains only water molecules. The tube is cooled to the freezing point of water. While the water is changing phase:

  1. its temperature decreases.
  2. the mean potential energy of the water molecules decreases.
  3. the mean kinetic energy of the water molecules decreases.
  4. the mean thermal energy of the water molecules decreases.
Answer

B.

Video Solution

Done Under 90

Question 11

The albedo of ice that covers a lake during winter is 0.75. This means that:

  1. the ice reflects 75 % of the radiation that is incident on its surface.
  2. the ice reflects 25 % of the radiation that is incident on its surface.
  3. 75 % of the radiation that is emitted by the ice falls into the ultraviolet region of the electromagnetic spectrum.
  4. 25 % of the radiation that is emitted by the ice falls into the ultraviolet region of the electromagnetic spectrum.
Answer

A.

Video Solution

Done Under 90

Question 12

The reservoirs of a Carnot engine are maintained at temperatures of 200\:^{\circ}\textup{C} and 300\:^{\circ}\textup{C}, respectively.

What is the best estimate for the efficiency of the engine?

  1. 0.17
  2. 0.33
  3. 0.67
  4. 0.83
Answer

A.

Video Solution

Done Under 90

Question 13

The internal resistance of a 32 V battery is 4.0\: \Omega. A lightbulb has three times the resistance than the internal resistance of the battery. The lightbulb is connected to the battery. Which of the following statements is incorrect for the circuit?

  1. The power dissipated in the lightbulb is 48 W.
  2. The potential difference across the lightbulb is 32 V.
  3. The total resistance in the circuit is 16\: \Omega.
  4. The current in the battery is 2.0 A.
Answer

B.

Video Solution

Done Under 90

Question 14

The specific heat capacity of a substance in the solid state is c and the specific latent heat of fusion of the substance is L. When 5000 J of energy is supplied to m kg of this substance in the solid state, the temperature of the substance increases by 50 K. When 20000 J of energy is supplied to \frac{m}{2} kg of this substance in the solid state at its melting point, the substance completely melts without a change in its temperature. What is the ratio \frac{c}{L}?

  1. 0.010 K
  2. 0.0025 K
  3. 0.010 K^{-1}
  4. 0.0025 K^{-1}
Answer

D.

Video Solution

Done Under 90

Question 15

Containers C and D contain the same ideal gas. The gas in container C is at a temperature of 500 K. The pressure in C is a third of the pressure in D. The volume of C is five times the volume of D. There are four times as many molecules in D than in C. What is the temperature in D?

  1. -198 ^{o}C
  2. 75 ^{o}C
  3. 348 ^{o}C
  4. 1200 ^{o}C
Answer

A.

Done Under 90

Question 16

The diagram shows cycle ABCDA for an ideal gas.

Work is done by the gas during

  1. changes BC and CD.
  2. changes DA and AB.
  3. changes BC and DA.
  4. changes AB and CD.
Answer

A.

Video Solution

Done Under 90

Question 17

Two resistors, X and Y, are connected as shown on the diagram. The ammeter and the voltmeter are ideal and the cell has negligible internal resistance.

What happens to the ammeter reading and the voltmeter reading when the resistance of resistor Y is halved?

Ammeter reading

Voltmeter reading

A. Increases Increases
B. Increases Decreases
C. Decreases Increases
D. Decreases Decreases
Answer

A.

Video Solution

Done Under 90

Question 18

A mass-spring system oscillates with simple harmonic motion (SHM). What is true about the restoring force that acts on the system?

  1. It is proportional to the amplitude of the oscillations.
  2. It is pointing in the opposite direction to the displacement for half of the period.
  3. It is proportional to the displacement from the equilibrium position.
  4. It is pointing away from the equilibrium position.
Answer

C.

Video Solution

Done Under 90

Question 19

In a double-slit experiment monochromatic violet light is incident on two slits that are located at a distance d from a screen. The separation of the slits is s. The distance between consecutive dark fringes in the interference pattern that forms on the screen is a

The experiment can be modified in the following ways:

I. Changing violet light to yellow light.

II. Decreasing d.

III. Decreasing s.

Which of these modifications will cause a to increase?

  1. I and II only
  2. I and III only
  3. II and III only
  4. I, II and III
Answer

B.

Video Solution

Done Under 90

Question 20

The displacement of a particle in a traveling wave varies with time as shown on the graph. What are the amplitude and the frequency of the particle’s motion?

Amplitude / nm

Frequency / MHz

A. 0.7 50
B. 70 0.05
C. 0.7 0.05
D. 70 50
Answer

B.

Video Solution

Done Under 90

Question 21

Three statements about single-slit diffraction are:

I. The angular width of the central maximum is twice that of the secondary maxima.

II. The intensity of the first diffraction maximum is approximately 5 % of the intensity of the central maximum.

III. When white light is incident on the slit, each  secondary maxima has the colours of the visible part of the electromagnetic spectrum.  

Which of these statements are correct?

  1. I and II only
  2. I and III only
  3. II and III only
  4. I, II and III
Answer

D.

Video Solution

Done Under 90

Question 22

A third-harmonic standing sound wave is formed in a pipe that is open at one end and closed at the other end. The length of the pipe is 1.2 m. Point X is located 20 cm from the closed end of the pipe and point Y is located 60 cm from the closed end of the pipe. What is the phase difference between the motion of a particle at point X and the motion of a particle at point Y?

  1. 0
  2. \frac{\pi}{4}
  3. \frac{\pi}{2}
  4. \pi
Answer

A.

Video Solution

Done Under 90

Question 23

A truck is accelerating towards a stationary observer at a constant rate and sounds a whistle with frequency f_{w}. When the truck passes the observer at time t_{p}, it begins to decelerate at a constant rate. Which graph correctly shows how f_{o}, the frequency detected by the observer varies with time?

Answer

A.

Video Solution

Done Under 90

Question 24

The gravitational force acting between two objects is F. The mass of each object is m and the distance between the objects is x. What will be the gravitational force acting between two objects that each have a mass of 2m when the distance between them is 2x?

  1. \frac{F}{4}
  2. \frac{F}{2}
  3. F
  4. 2F
Answer

C.

Video Solution

Done Under 90

Question 25

A proton, moving with initial velocity v, enters an electric field between two parallel, horizontal plates near the surface of the Earth. The velocity of the proton does not change as it moves through the electric field. What is the direction and the best estimate for the magnitude of the electric field between the plates?

Electric field direction between the plates

Magnitude of electric field between the plates

A. Upwards 100 nN C^{-1}
B. Upwards 10 nN C^{-1}
C. Downwards 100 nN C^{-1}
D. Downwards 10 nN C^{-1}
Answer

A.

Video Solution

Done Under 90

Question 26

A proton moves in an electric field. Which of the following paths requires the electric field to do the most work?

Answer

D.

Video Solution

Done Under 90

Question 27

The gravitational potential energy of a space telescope orbiting a planet at a distance R from the surface of the planet is E and the weight of the space telescope is W. The radius of the planet is R. What are the gravitational potential energy and the weight of the satellite at the surface of the planet?

Gravitational potential energy

Weight

A. 2E 2W
B. 2E 4W
C. 4E 2W
D. 4E 4W
Answer

B.

Video Solution

Done Under 90

Question 28

Moon A has mass M, radius R and the gravitational field strength on the surface of Moon A is g. Moon B has mass 3M and the gravitational field strength on its surface is \frac{g}{4}.

What is the diameter of Moon B?

  1. 2\sqrt{3}R
  2. 4\sqrt{3}R
  3. 12R
  4. 24R
Answer

B.

Video Solution

Done Under 90

Question 29

Three equipotential surfaces are shown around a negative point charge. The potential difference between two consecutive equipotential surfaces is 30 V.

What is the direction of the electric field and what is the total work done when a positive charge 2 mC is moved from A to B and then to C?

Direction of the electric field

Total work done when moving a positive charge from A to B and then to C

A. Away from the negative charge 0
B. Away from the negative charge 240 mJ
C. Towards the negative charge 0
D. Towards the negative charge 240 mJ
Answer

C.

Video Solution

Done Under 90

Question 30

A conducting coil is rotating in a magnetic field. The graph shows how the induced emf in the coil varies with time

Which of the following gives two times when the magnetic flux through the coil is zero?

  1. 0 and t = T
  2. t = \frac{T}{2} and t = T
  3. t = \frac{T}{4} and t = \frac{3T}{4}
  4. t = \frac{T}{2} and t = \frac{3T}{4}
Answer

C.

Video Solution

Done Under 90

Question 31

The radius of a planet is 4 \times 10^6 m and the escape speed for the planet is 10^4 m s^{-1}.

What is the mass of the planet?

  1. \frac{2 \times 10^{14}}{G}
  2. \frac{4 \times 10^{14}}{G}
  3. \frac{2 \times 10^{22}}{G}
  4. \frac{4 \times 10^{22}}{G}
Answer

A.

Video Solution

Done Under 90

Question 32

Coil P and coil Q are rectangular coils. The areas of the coils are parallel. There is an anticlockwise direct current in coil P as shown on the diagram. Coil Q is first moved towards coil P, then away from coil P.

What is the direction of the induced current between points A and B when coil Q is moving towards and away from coil P?

Induced current between A and B when coil Q is moving towards coil P

Induced current between A and B when coil Q is moving away from coil P

A. Towards the left Towards the right
B. Towards the left Towards the left
C. Towards the right Towards the right
D. Towards the right Towards the left
Answer

A.

Video Solution

Done Under 90

Question 33

The nucleon number of element A is N_{A} and its nuclear density is \rho_{A}. The nucleon number of element B is \frac{N_{A}}{2} and its nuclear density is \rho_{B}. What is \frac{\rho_{A}}{\rho_{B}}?

  1. 1
  2. 2
  3. 4
  4. 8
Answer

A.

Video Solution

Done Under 90

Question 34

The initial number of undecayed nuclides in a radioactive sample is N. Which graph correctly shows how N varies with time?

Answer

B.

Video Solution

Done Under 90

Question 35

The diagram shows a simple model of the four energy levels in an atom.

What is the best estimate for the smallest and for the largest frequency in the absorption spectrum of the atom?

Smallest frequency in absorption spectrum

Largest frequency in absorption spectrum

A. 2.0 PHz 6.0 PHz
B. 2.0 PHz 12 PHz
C. 0.50 PHz 6.0 PHz
D. 0.50 PHz 12 PHz
Answer

B.

Video Solution

Done Under 90

Question 36

Under what temperature and density conditions does fusion take place in stars?

Temperature

Density

A.

Low

Low

B.

Low

High

C.

High

Low

D.

High

High

Answer

D.

Video Solution

Done Under 90

Question 37

Monochromatic light is incident on a metal plate. As a result, photoelectrons are emitted from the surface of the plate. 

Which graph correctly shows the relationship between \lambda, the wavelength of the incident light and E, the kinetic energy of the emitted photoelectrons?

Answer

A.

Video Solution

Done Under 90

Question 38

The initial activity of a radioactive sample is 160 Bq and the background activity at this location is 25% of the initial activity of the sample. The half-life of the radioactive nuclide is 7 hours.

What is the activity detected at the location of the sample after 21 hours?

  1. 25 Bq
  2. 40 Bq
  3. 60 Bq
  4. 80 Bq
Answer

C.

Video Solution

Done Under 90

Question 39

A moderator and control rods are two key parts of a nuclear power station. What is true about the atoms in a moderator and the atoms in control rods?

  1. Both are good absorbers of neutrons.
  2. Both are poor absorbers of neutrons.
  3. Moderator atoms are good absorbers of neutrons, control rod atoms are poor absorbers of neutrons.
  4. Moderator atoms are poor absorbers of neutrons, control rod atoms are good absorbers of neutrons.
Answer

D.

Video Solution

Done Under 90

Question 40

The initial activity of a pure sample of a radioactive nuclide is 6.0 \times 10^{5} Bq. The half-life of the nuclide is 10 s. What is the best estimate for the activity of the sample after 15 s?

  1. 1.5 \times 10^{5} Bq
  2. 2.1 \times 10^{5} Bq
  3. 2.8 \times 10^{5} Bq
  4. 3.0 \times 10^{5} Bq
Answer

B.

Video Solution

Done Under 90

Paper 1B

20 marks

Question 1

A student carries out an investigation to determine the relationship between the tension T in a wire of fixed length and the frequency f of the fundamental vibration of a standing wave on the wire.

For T = 10 N, the student measures the frequency five times and records the following values:

f / Hz 182 185 152 182 180

The student then carries out two different calculations for the mean value of f and obtains 176.2 Hz and 182 Hz.

(a)   Comment on these mean values.

[2]

The graph of f against T is plotted.

(b)   The uncertainty in T is \pm 5\% and the uncertainty in f is \pm 20 Hz.

(i)   Draw error bars for the data point where T = 40 N.

[2]

(ii)   Calculate the largest percentage uncertainty in f for these data values.

[2]

The student hypothesizes that the relationship between T and f can be described as f = A\sqrt{T} where A is a constant. 

(c)   

(i)   Find the fundamental SI unit for A.

[2]

(ii)   Write down a pair of quantities that the student can plot in order to test the hypothesis.

[1]

(iii)   Using the data point where T = 10 N, determine the uncertainty in A.

[3]

Answer 1a

The mean value 176.2 is quoted incorrectly to four significant figures. It should be quoted to three significant figures.

The outlier (152) is included in the calculation of 176.2, but not in the calculation of 182.

 

Video Solution 1a

Coming soon!

Answer 1b(i)

 

 

Video Solution 1b(i)

Coming soon!

Answer 1b(ii)

The largest percentage uncertainty occurs at the smallest value of f, so at f = 182 Hz

Calculating the percentage uncertainty for f = 182 Hz:

\frac{\Delta f}{f} = \frac{20}{182} \approx 0.11 = 11\%

Video Solution 1b(ii)

Coming soon!

Answer 1c(i)

The fundamental SI unit of f is \textup{s}^{-1} and the fundamental SI unit of T is \textup{kg\,m\,s}^{-2}

Therefore the fundamental SI unit of A is:

\frac{\textup{s}^{-1}}{\left (\textup{kg\,m\,s}^{-2}  \right )^{\frac{1}{2}}} = \textup{kg}^{-\frac{1}{2}}\, \textup{m}^{-\frac{1}{2}}

 

Video Solution 1c(i)

Coming soon!

Answer 1c(ii)

f against \sqrt{T}

OR

f^{2} against T

 

Video Solution 1c(ii)

Coming soon!

Answer 1c(iii)

Calculating A:

A = \frac{182}{\sqrt{10}} \approx 57.6

Calculating the fractional uncertainty in A:

\frac{\Delta A}{A} = \frac{20}{182} + \frac{1}{2} \times 0.05 \approx 0.135

Calculating the uncertainty in A:

\Delta A = 57.6 \times 0.135 \approx 8

 

Video Solution 1c(iii)

Coming soon!

Question 2

A student carries out an experiment to find the internal resistance r and the electromotive force (emf) \varepsilon of a cell. The student uses a circuit to measure the terminal potential difference V and current I.

The uncertainty in the measurement of each value of I is \pm 2 mA and the uncertainty in the measurement of each value of V is \pm 0.04 V.

The data collected by the student is plotted on a graph.

(a)

(i)   State and explain why no horizontal error bars are shown for the data points.

[2]

(ii)   Draw the line of best fit for the data.

[1]

(b)   For this investigation V = -Ir + \varepsilon.

        Using the graph

(i)   find the internal resistance of the cell. Give your answer together with an appropriate unit. 

[3]

(ii)   determine the emf of the cell along with its uncertainty and give your answer in an appropriate format.

[2]

Answer 2a(i)

Horizontal error bars would show the uncertainty in the current.

Since the uncertainty in the current is very small (negligible), there is no need to show error bars for the current.

Answer 2a(ii)

 

 

Video Solution 2a

Answer 2b(i)

The internal resistance of the cell is shown by the gradient of the line of best fit. 

We can calculate this gradient using the approximate coordinates of two points on this line, so for example:

(250, 2.80) and (1240, 2.40)

We will carry out the calculations using amperes for the current.

\textup{gradient} = \frac{2.40 - 2.80}{1240 \times 10^{-3} - 250 \times 10^{-3}} \approx -0.404

Therefore r \approx 0.404\: \Omega

 

Answer 2b(ii)

The emf of the cell is shown by the vertical axis intercept of the graph.

The vertical axis intercept is approximately 2.89, therefore, using the uncertainty value in V we get:

\varepsilon \approx (2.89 \pm 0.04) V

 

Video Solution 2b