Black Hole

Basic

Moderate

Challenging

Difficult

Black Hole

Question 1 

The time it takes for light to cross a helium nucleus is approximately:

1. 10^{-7} s
2. 10^{-15} s
3. 10^{-21} s
4. 10^{-23} s

Question 2 

Which of the following is a fundamental SI unit?

1. Ampere
2. Joule
3. Newton
4. Coulomb

Question 3 

A cube-shaped container is filled with 1000 litres of water. The density of water 1 g cm^{-3}. The difference in the orders of magnitude of the diameter of a water molecule and the side length of the container is:

1. 14
2. 12
3. 10
4. 8

Question 4 

Which of the following units is equivalent to W m^{-1}?

1. kg m s^{-2}
2. kg m^{2} s^{-2}
3. kg m s^{-3}
4. kg m^{2} s^{-3}

Question 5 

The fundamental SI unit combination for volt is:

1. kg m^{2} A^{-1} s^{-2}
2. kg m^{2} A^{-1} s^{-3}
3. kg m^{2} C^{-1} s^{-2}
4. kg m^{2} C^{-1} s^{-3}

Question 6 

The best estimate for the order of magnitude of the ratio \frac{electron \:  rest \: mass}{neutron \:  rest \:  mass} is:

1. -3
2. 3
3. -4
4. 4

Question 7 

Work done per unit volume has the same units as:

1. Impulse
2. Specific energy
3. Force
4. Pressure

Question 8 

An object of mass 0.0250 kg starts accelerating from rest and reaches a speed of 25.82 m s^{-1}. What is the change in the kinetic energy of the object?

1. 8 J
2. 8.3 J
3. 8.33 J
4. 8.333 J

Question 9 

The charge of a proton is:

1. 1.60 \times 10^{-34} PC
2. 1.60 \times 10^{-22} mC
3. 1.60 \times 10^{-13} MC
4. 1.60 \times 10^{-4} pC

Question 10 

An apple is released from rest near the surface of the Earth. It hits the ground after 2 s. What is the best estimate for the apple’s momentum right before it hits the ground?

1. 3 \times 10^{0} kg m s^{-1}
2. 3 \times 10^{1} kg m s^{-1}
3. 3 \times 10^{2} kg m s^{-1}
4. 3 \times 10^{3} kg m s^{-1}