The S.I unit of work done is ……….
a) Watt
b) Newton
c) Pascal
d) joule
Explanation: The S.I unit of work is joule abbreviated J, and named in honor of the 19th century English physicist James Prescott Joule.
1joule =………….
a) 1N.s
b) 1N.s2
c) 1N.m
d) 1N.m2
Explanation: W = F x s So, 1joule = 1newton x 1 meter
Work done is a ………quantity.
a) basic
b) derived
c) scalar
d) vector
In work done the ……component of applied force is in the direction of motion.
a) parallel
b) effective
c) vertical
d) anti parallel
When the applied force is making an angle θ
with displacement , then work done can be written as ……….
a) W = Fcos θ x r
b) W = Fsin θ x v
c) W = Fcos θ x s
d) W = Fsin θ x s
When a body falls freely under
gravity, then the work done by the gravity is………….
a) positive
b) negative
c) zero
d) none of these
Explanation: If a force acting on a body has a component in the direction of displacement, then the work done by the force is positive. Hence when a body falls freely under the influence of gravity the work done by the gravity is positive.
