A particle P is projected vertically upwards with speed from a point on the ground.
Find the greatest height above the ground reached by P.
Find the total time from projection until P returns to the ground.
EduNinjaA particle P is projected vertically upwards with speed 20 m s−1 from a point on the ground.
Find the greatest height above the ground reached by P.
Find the total time from projection until P returns to the ground.
A particle of mass 0.2 kg moving in a straight line experiences a constant resistance force of 1.5 N . When the particle is moving at speed 2.5 m s−1, a constant force of magnitude F N is applied to it in the direction in which it is moving. Given that the speed of the particle 5 seconds later is 4.5 m s−1, find the value of F.
Two particles A and B, of masses 0.8 kg and 0.2 kg respectively, are connected by a light inextensible string that passes over a fixed smooth pulley. The particles hang vertically. The system is released from rest. Show that the acceleration of A has magnitude 6 m s−2 and find the tension in the string.
A particle of mass 0.2 kg is resting in equilibrium on a rough plane inclined at 20∘ to the horizontal.
The coefficient of friction between the particle and the plane is 0.6 . A force of magnitude 0.9 N is applied to the particle down a line of greatest slope of the plane. The particle accelerates down the plane.
Find this acceleration.
A block of mass 3 kg is initially at rest on a smooth horizontal floor. A force of 12 N , acting at an angle of 25∘ above the horizontal, is applied to the block. Find the distance travelled by the block in the first 5 seconds of its motion.
A particle of mass 2 kg is initially at rest on a rough horizontal plane. A force of magnitude 10 N is applied to the particle at 15∘ above the horizontal. It is given that 10 s after the force is applied, the particle has a speed of 3.5 m s−1.
Show that the magnitude of the frictional force is 8.96 N , correct to 3 significant figures.

Two particles P and Q, of masses 0.6 kg and 0.4 kg respectively, are connected by a light inextensible string. The string passes over a small smooth light pulley fixed at the edge of a smooth horizontal table. Initially P is held at rest on the table and Q hangs vertically (see diagram). P is then released. Find the tension in the string and the acceleration of Q.
A particle moves up a line of greatest slope of a rough plane inclined at an angle α to the horizontal, where sinα=0.28. The coefficient of friction between the particle and the plane is 31.
Show that the acceleration of the particle is −6 m s−2.
A straight ice track of length 50 m is inclined at 14∘ to the horizontal. A man starts at the top of the track, on a sledge, with speed 8 m s−1. He travels on the sledge to the bottom of the track. The coefficient of friction between the sledge and the track is 0.02 . Find the speed of the sledge and the man when they reach the bottom of the track.
A block is at rest on a rough horizontal plane. The coefficient of friction between the block and the plane is 1.25 .
Given that the weight of the block is 60 N , find the value of P when the acceleration of the block is 4 m s−2.