Physics questions and answers

Physics Questions and Answers

If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.

1,896.

The lower and upper fixed point of a thermometer are 30mm and 180mm respectively. Calculate the temperature in degrees Celsius when the thermometer reads 45mm

A.

10.0oC

B.

15.0oC

C.

20.0oC

D.

30.0oC

Correct answer is A

100....180
A......45
0......30

\(\frac{45 - 30}{180 - 30} = \frac{A - 0}{100 - 0}\)

A = \(\frac{15 \times 100}{150} = 10^oC\)

1,897.

Which of the following source of energy is renewable?

A.

sun

B.

petroleum

C.

coal

D.

uranium

Correct answer is A

No explanation has been provided for this answer.

1,898.

Which of the following quantities has the same unit as energy?

A.

power

B.

work

C.

force

D.

momentum

Correct answer is B

No explanation has been provided for this answer.

1,899.

Fuel was consumed at a steady rate of 5.0 x 10-2kg per second in a rocket engine and ejected as a gas with a speed of 4 x 103ms-1. Determine the thrust on the rocket

A.

20N

B.

80N

C.

200N

D.

800N

Correct answer is C

F = ma = \(\frac{mv}{t} = \frac{5 \times 10^{-2} \times 4 \times 10^{3}}{1}\)

= 200N

1,900.

A body of mass 5kg moving with a velocity of 10ms-1 collides with a stationary body of mass 6kg. If the two bodies stick together and move in the same direction after their collision, calculate their common velocity

A.

4.55ms-1

B.

12.00ms-1

C.

30.00ms-1

D.

50.00ms-1

Correct answer is A

\(M_1V_1 + M_2U_2 = V(M_1 + M_2)\)

5 x 10 + 6 x 0 = V(5 + 6)

V = \(\frac{50}{11} = 4.55\)m/s