Question

GOLD PACKAGE
6.
a) 2my2
A body of mass ‘m' moving along the circumference of a circle of radius 'r' with uniform speed u
completes half the revolution. The work done is
b) amy2
c) zero
d) 4mv2
7. A particle moves from a point 7; = (2m) { +(3m) î to another point F, = (3m)i +(2m) į during whic
certain force F =(5N)i +(5N); acts on it. The work done by the force on the particle during 2
displacement is
a) 10 J
b) 50J
c) zero
d) 0.5 J
I
PLATINUM PACKAGE
8.
A block of mass 250 g slides down an incline of inclination 37° with a uniform speed. Work
agains






t the friction as the block slides through 1.0 m is
a) 1.5 J
b) 15 J
c) 150J
d) 0.15 J​

Answer 1

Answer:

ans-8

1.5 J

Explanation:

Component of acceleration towards displacement =gsin37

0

=

5

3g

=6 m/s

2

Force in the direction of displacement , F=ma

=0.25×6

=1.5N

Work done against the friction ,W=F s=1.5×1=1.5 J