Question

An object moving at 36 km/h reduces its speed to 18 km/h in 2sec. If the mass of
the object is 20 kg, find the average force acting on the object.

Answer 1

Answer:

u = 36km/h

v = 18km/h

t = 2 sec

mass = 20 kg

f = m(v-u)/t

f = 20*18-36/2

     -180N

Explanation:

Answer 2

Answer:

Given : Mass of earth M=6×10

24

kg

Mass of object m=1 kg

Radius of earth R=6.4×10

6

m

Force of gravitation between them, F=

R

2

GMm

F=

(6.4×10

6

)

2

6.67×10

−11

×(6×10

24

)×1

=9.77 N