Question

STD 10 science 1 solved projects

Answer 1

Answer:

the indefinite continued progress of existence and events in the past, present, and future regarded as a whole.

"travel through space and time"

Answer 2

(b) While carrying a load, the donkey has to apply a force in the upward direction. But, displacement of the load is in the forward direction. Since displacement is perpendicular to force, the work done is zero.

(c) A windmill works against the gravitational force to lift water. Hence, work is done by the windmill in lifting water from the well.

(d) In this case, there is no displacement of the leaves of the plant. Therefore, the work done is zero.

(e) An engine applies force to pull the train. This allows the train to move in the direction of the force. Therefore, there is a displacement in the train in the same direction. Hence, work is done by the engine on the