Processing math: 100%
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.

2,906.

An object of mass 50kg is released from a height of 2m.Find the kinetic energy just before it strikes the ground

A.

250J

B.

1000J

C.

10 000J

D.

100 000J

Correct answer is B

P.E = K.E = mgh

= 50 x 10 x 2 = 1000J

2,907.

Which of the following is TRUE of a particle moving in a horizontal circle with constant angular velocity?

A.

The energy is costant but the linear momentum varies

B.

The linear momentum is conatant but the energy varies

C.

both energy and linear momentum are constant

D.

The speed and the linear velocity are both constant

Correct answer is C

No explanation has been provided for this answer.

2,908.

A motor vehicle is brought to rest from a speed of 15ms-1 in 20 seconds. Calculate the retardation.

A.

0.75ms-1

B.

1.33ms-2

C.

5.00ms-2

D.

7.50ms-2

Correct answer is A

Retardation = uvt

= 15020

= 0.75ms-1

2,909.

An object is projected with a velocity of 80ms-1 at an angle of 30o to the horizontal.The maximum height reached is

A.

20m

B.

80m

C.

160m

D.

320m

Correct answer is B

max. height = U2sin2θ2g

= 80×80×sin2(30)2×10

= 80m

2,910.

A boat travels due east at a speed 40ms-1s across a river flow due south at 30ms-1s. What is the resultant speed of the boat?

A.

1.3ms-1

B.

10.0ms-1

C.

50.0ms-1

D.

70.0ms-1

Correct answer is C

No explanation has been provided for this answer.