Advertisements
Advertisements
प्रश्न
What is the work done against gravity when a body is moved horizontally along a frictionless surface?
Advertisements
उत्तर
When a body is moved horizontally along a frictionless surface, the work done against gravity is zero because the direction of motion of the body is perpendicular to the direction of the gravitational force.
APPEARS IN
संबंधित प्रश्न
Give reasons for the following A teacher moving around in the class is doing work but a child standing and reading a book is not doing any work.
A bullet of mass 0.5 kg slows down from a speed of 5 m s-1 to that of 3 m s-1. Calculate the change in kinetic energy of the ball.
State two disadvantages of producing hydroelectricity.
A 100 W electric lamp emits energy in the form of light at the rate 10 J per second. What percentage of electric energy does the lamp transform into light energy?
A woman pulls a bucket of water of total mass 5 kg from a well which is 10 s. calculate the power used by her.
An electric motor pump is 60% efficient and is rated 2.5 H.P. Calculate the maximum load it can lift through a height of 10m in 8 sec. (1 H.P. = 750 W).
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
A donkey is carrying a load on its back.
