PART - 1 CH - 2 Motion in a Straight Line — Physics STD 11 Science — Question

The sign of work done by a force on a body is important to understand. State carefully if the following quantities are positive or negative: Work done by friction on a body sliding down an inclined plane.

A lift is accelerated upward. Will the apparent weight of a person inside the lift increases, decreases or remains the same relative to its real weight? If the lift is going with uniform speed, then?

A cubical block of ice floating in water has to support a metal piece weighing 0.5kg. What can be the minimum edge of the block so that it does not sink in water? Specific gravity of ice = 0.9.

If the length of a wire is cut to half then what would be the effect on the maximum weight which it bears?

A ferry boat loaded with rocks has to pass under a bridge. The maximum height of the rocks is slightly more than the height of the bridge so that the boat just fails to pass under the bridge. Should some of the rocks be removed or some more rocks be added?

Read each statement below carefully and state, with reasons and examples, if it is true or false: A scalar quantity is one that Can never take negative values.

Read each statement below carefully and state, with reasons, if it is true or false: The acceleration vector of a particle in uniform circular motion averaged over one cycle is a null vector.

Read each statement below carefully and state with reasons, if it is true or false: The average speed of a particle (defined as total path length divided by the time taken to cover the path) is either greater or equal to the magnitude of average velocity of the particle over the same interval of time.

A man wearing a watch is falling down from a tower, will the watch show the correct time?