Question

A box of mass 2 kg is placed on the
roof of a car. The box would remain
stationary until the car attains a
maximum acceleration. Coefficient of
static friction between the box and the
roof of the car is 0.2 and g = 10 ms?
This maximum acceleration of the car
for the box to remain stationary, is
1.8 ms
2.6 ms?
3.4 ms2
4.2 ms?​

Answer 1

Answer:2m/s^2

Explanation:for a=max

Frictional force f= max

f=max=coefficient of friction *Normal force (N)

=coefficient of friction*mg(=N)

=0.2*20=4

But max frictional force must be equal to Force which acts in opposite direction to itF=ma

f=ma

Putting the value of f=4

4= 2*a

a=4/2=2m/s^2