Question Text
Question 1 :
Food grains are getting dried in the sun. Is it a work?
Question 2 :
The potential energy of a freely falling object decreases progressively. Does this violate the law of conservation of energy?
Question 3 :
Four men lift a 250 kg box to a height of 1 m and hold it without raising or lowering it. How much work is done by the men in lifting the box? $(g=10 ms^{-2})$
Question 6 :
An object thrown at a certain angle to the ground moves in a curved path and falls back to the ground. The initial and final points of the object lie on the same horizonta line. What is the work done by the force of gravity on th object
Question 7 :
An object of mass 12 kg is at a certain height above the ground. If the potential energy of the object is 480 J, find the height at which the object is with respect to the ground. Given, g = 10 m $s^{-2}$.
Question 8 :
Find the energy possessed by an object of mass 10 kg when it is at a height of 6 m above the ground. Given, g = 9.8 m $s^{-2}$.
Question 9 :
Work done on an object is defined as the magnitude of the force multiplied by the distance moved by the object in the direction of the applied force. The unit of work is joule:$ 1 joule = 1 newton \times 1 metre.$ Is the statement true or false?
Question 10 :
A car is accelerated on a levelled road and attains a velocity 4 times of its initial velocity. In this process the potential energy of the car
