(a) What should be the angle between the direction of force and the direction of displacement, for work to be negative?
(b) Name the physical quantity obtained using the formula \frac{U}{h}, where U is the potential energy and h is the height.
(a) 180°
(b) As U=mgh, therefore \frac{U}{h} = mg. The physical quantity obtained is the weight of the object.
More ICSE Easy level questions
Calculate the power spent by a crane while lifting a load of mass 2000 kg, at velocity of 1.5 m s−1. (g = 10 m s−2).
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(a) Name the unit of work done used on the subatomic scale. (b) To which class of lever does a pair of scissors belong? (c) A stone is tied to a string and displaced from A to B by application of constant force F in three different ways as shown below. Arrange the three cases in ascending order of the work done by the force. (Given AJB is a semicircle, θ < 90° and AB = 20 m)
