Physics - Study Mode

[#721] When milk is churned, the cream separates from it due to:
Correct Answer

(B) Centrifugal force

Explanation

Solution: When Milk is churned vigorously the cream from it is separated out due to Centrifugal Force. Churning physically agitates the cream until it ruptures the fragile membranes surrounding the milk fat.

[#722] When the milk is churned vigorously the cream from it is separated out due to
Correct Answer

(D) Centrifugal force

Explanation

Solution: When Milk is churned vigorously the cream from it is separated out due to Centrifugal Force. Churning physically agitates the cream until it ruptures the fragile membranes surrounding the milk fat.

[#723] A man stands on the pan of a balance holding a fish in his right hand and bucket of water in his left hand. If he transfers the fish into the bucket, the total weight on the pan
Correct Answer

(C) Remains the same

Explanation

Solution: Before transferring the fish, the position is the man with the fish and the bucket of water. After transferring the position is: the man without the fish, but the fish inside the water in the bucket. Thus to know whether there is any change in weight, it is enough to consider whether there is any change in weight when the fish in air is transferred into the water. The answer is there is no change as when in water though it loses weight due to upthrust of water on it, the level of water increases and exerts an equal force at the bottom.So, (c) is correct.

[#724] A boy is swinging a ball attached to a string in a horizontal circle. If the string snaps
Correct Answer

(B) It will continue to travel along a tangent to the circle at the point the ball was at the time of snapping and finally fall down

Explanation

Solution: A boy is swinging a ball attached to a string in a horizontal circle. If the string snaps it will continue to travel along a tangent to the circle at the point the ball was at the time of snapping and finally fall down.

[#725] A body moving in a circular path with a constant speed has a
Correct Answer

(C) Constant kinetic energy

Explanation

Solution: A body moving in a circular path with a constant speed has a constant kinetic energy.