A body of mass 2 kg ,moving on a horizontal surface with an initial velocity of 4 m/s , comes to rest after 2 s.If one wants to keep this moving on the same surface with a velocity of 4 m/s,the force required is
2 N
4 N
6 N
10 N
A block of mass 2 kg rests on a rough inclined plane making an angle of 30° with the horizontal. The coefficient of static friction between the block and the plane is 0.7. The frictional force on the block is
9.8 N
0.7 x 9.8 x √3 N
9.8 x √3 N
0.7 x 9.8 N
A machine gun has a mass of 10 kg.It fires 30 g bullets at the rate of 6 bullets per second with a speed of 400 m/s.What force must be applied to the gun to keep it in position ?
72 N
75 N
82 N
97 N
A force of 100 N need to be applied parallel to a smooth inclined plane just to hold a body on it. The angle of inclination of the inclined plane is 300. How much horizontal force need to be applied to do the same?
50 N
87 N
100 N
115 N
Consider a car moving along a straight horizontal road with a speed of 72 km/hr.If the coefficient of static friction between the tyres and the road is 0.5,the shortest distance in which the car can be stopped is
(Take g = 10 m/s2)
30 m
40 m
72 m
20 m
A boy of mass 50 kg is standing on a weighing machine placed on the floor of a lift.The machine reads his weight in Newtons.What is the reading of the machine if the lift is moving upwards with a uniform speed of 10 m/sec2?
(g = 10 m/sec2 )
510 N
480 N
490 N
500 N
A body is at rest on the surface of the earth. Which of the following statement is correct?
No free is acting on the body
Only weight of the body acts on it.
Net downward force is equal to the net upward force.
None of the above statement is correct
Friction is the result of
gravitational acceleration
molecular interaction
magnetic interaction
nuclear interaction
A smooth inclined plane has length 10 m and the angle of inclination is 300. A body of mass 2 kg is released from rest at the top of the inclined plane. What is its acceleration down the inclined plane?
10 ms-2
5√3 ms-2
5 ms-2
20/√3 ms-2
A force of 15 Newton acts on a body of weigh 30 Newton. What is the acceleration produced in metres per second?
Take g = 10ms-2.
15.00
5.00
1.50
0.50