Motion, Gravitational Field, and Equilibrium of Forces
A car of mass 1500kg goes round a circular curve of radius 50m at a speed of 40ms-1 . The magnitude of the centripetal force on the car is
1.2 x 103N
4.8 x 104N
1.2 X 102 N
4.8 X 103 N
Two spheres of masses 5.0kg and 10.0kg are 0.3m apart. Calculate the force of attraction between them.
4.00 x 10-2 N
3.57 X 10-2 N
3.71 X 10-8 N
3.50 X 10-10 N
A motorcyclist travelling at 30 ms-1 starts to apply his brakes when he is 50 m from the traffic light that has just turned red. If he just reached the traffic light, his deceleration is
5 m s-2
9 m s-2
10 m s-2
18 m s-2
An object is projected from a height of 80 m above the ground with a velocity of 40 m s-1 at an angle of 30° to the horizontal. The time of flight is
In the figure below, the coefficient of static friction is 0.5. If the tension in the string is T, the acceleration of the system in motion is
A force of 100N is used to kick a football of mass 0.8kg. Find the velocity with which the ball moves if it takes 0.8s to be kicked
A body weighing 80N stands in an elevator that is about to move. The force exerted by the floor on the body as the elevator moves upwards with an accelerator of 5 ms-2 is
A particle in circular motion performs 30 oscillations in 6 seconds. Its angular velocity is
10π rad s-1
5π rad s-1
6 rad s-1
5 rad s-1
A catapult used to hold a stone of mass 500 g is extended by 20 cm with an applied force F. If the stone leaves with a velocity of 40 ms-1 , the value of F is
4.0 X 104 N
4.0 X 103 N
2.0 X 103 N
4.0 X 102 N
The velocity v of a particle in a time t is given by the equation v = 10 + 2t2. Find the instantaneous acceleration after 5 seconds
A rope of being used to pull a mass of 10 kg vertically upward. Determine the tension in the rope if, starting from rest, the mass acquires a velocity of 4 ms-1 in 8s. ( g = 10ms-2)
A stream is flowing at 0.75 ms-1 and a boat heading perpendicular for the stream landed at the opposite bank at angle 30°. Calculate the velocity of the boat .
The diagram below shows the velocity-time graph of a vehicle. Its acceleration and retardation respectively are
8.0 ms-2 and 4.0 ms-2
4.0 ms-2 and 8.0 ms-2
4.0 ms-2 and 2.0 ms-2
2.0 ms-2 and 4.0 ms-2
A particle of mass 10-2 kg is fixed to the tip of a fan blade which rotates with angular velocity of 100 rad s-1 if the radius of the blade is 0.2m, the centripetal force is
A ball is moving at 18 ms-1 in a directional inclined at 60°C to the horizontal. The horizontal component of its velocity is
6 √3 ms-1
A ball of mass 0.15 kg is kicked against a rigid vertical wall with a horizontal velocity of 50 ms-1. If it rebounced with a horizontal velocity of 30 ms-1, calculate the impulse of the ball on the wall.
The force of attraction between two point masses is 10-4 when the distance between them is 0.18m . If the distance is reduced to 0.06m, calculate the force
1.1 x 10-5N
3.3 x 10-5N
3.0 x 10-4N
9.0 x 10-4N
A bullet fired at a wooden block of thickness 0.15m manages to penetrate the block. If the mass of the bullet is 0.025 kg and the average resisting force of the wood is 7.5 X 103 N, calculate the speed of the bullet just before it hits the wooden block.
At what respective values of x, y and z would the unit of force, the newton, be dimensionally equivalent to MxLyTz ?
-1, 1 ,2
1 , 1, -2
1, -1, 2
-1, 1, -2
The distance xm traveled by a particle in time t seconds is described by the equation x = 10 + 12t2. Find the average speed of the particle between the time interval t= 2s and t =5s
An arrow of ma0.1 kg moving with a horizontal velocity of 15 ms-1 is shot into wooden block of mass 0.4kg lying at rest on a smooth horizontal surface. Their common velocity after impact is
A body of mass 2 kg moving vertically upwards has its velocity increased uniformly from 10 ms-1 to 40 ms-1 in 4s. Neglecting air resistance, calculate the upward vertical force acting on the body .
A planet has mass m1, and is at a distance r1 from the sun. A second planet has mass m2 = 10m1 and is at a distance of r2 = 2r1 from the sun. Determine the ratio of the gravitational forces experienced by the planets.
1 : 5
2 : 5
4 : 5
For what value of θ are the forces in the diagram beside in equilibrium?
The velocity-time graph of a body moving in a straight line and decelerating uniformly to rest is represented by
The acceleration of the system shown below is
The length of a displaced pendulum bob which passes its lowest point twice every second is
0. 45 m
What is the acceleration due to gravity 'g' on the moon, if g is 10 m-2 on the earth?
A body is projected from the earth's surface with the intension of letting it escape from the earth's gravitational field. What is the minimum escape velocity of the body?
14 km s-1
13 km s-1
12 km s-1
11 km s-1
A boat travels due east at a speed of 40 ms-1 across a river flowing due south at 30ms-1. What is the resultant speed of the boat?
An object is projected with a velocity of 80 ms-1 at an angle of 30° to the horizontal. The maximum height reached is
A motor vehicle is brought to rest from a speed of 15 ms-1 in 20 seconds . Calculate the retardation