Physics MCQS

171. A ball is thrown vertically upward. Its velocity at the highest point is?
A. Zero
B. One
C. Two
D. None of the above

172. _ is a vector quantity?
A. Speed
B. Distance
C. Displacement
D. Power

173. The SI unit of pressure is Pascal which is equal to?
A. 1 Nm^-2
B. 10^2 Nm^-2
C. 10^3 Nm^-2
(D) 10³Nm_-2

Certainly! Here are the additional questions with the correct answers in bold, the removal of the asterisk sign, and each question separated by a line:

174. The Centripetal force for a car moving on a road is given by :
A. Friction due to tires
B. Force of brakes
C. The driver of the car
D. Force by the steering wheel

175. If the earth were to rotate faster, than its present speed the weight of an object will :
A. It goes up at the equator but stays the same at the poles.
B. It goes down at the equator but stays the same at the poles.
C. It stays the same at the decrease but goes down at the poles.
D. It stays the same at the equator but goes up at the poles.

176. Centre of mass is a point :
A. Which is the geometric centre of a body
B. At what distances are the particles identical?
C. Where the whole mass of the body is supposed to be centered
D. Which is the origin of the reference frame

177. What will be the duration of the day and night (in hours) if the diameter of the earth is suddenly reduced to half its original value, the mass remaining constant?
A. 12
B. 6
C. 3
D. 2

178. A person standing on a rotating platform has his hands lowered. He suddenly outstretches his arms. The angular momentum :
A. Becomes zero
B. Increases
C. Decreases
D. Remains the same

179. A 500 kg car takes a round turn of radius 0 m with a velocity of 36 km/h. The centripetal force is :
A. 250 N
B. 750 N
C. 1000 N
D. 1200 N

180. Coin of radius R is beaten uniform to make a disc of radius 2R. Its moment of inertia :
A. Decreases
B. Increases
C. Remains the same
D. Decreases or increases depending on the actual value