9231/32 · May/June 2026
Download PDFAn object consists of a uniform solid hemisphere of radius attached to a uniform solid cylinder of radius and height . The hemisphere and the cylinder are made of the same material. The axes of symmetry of the hemisphere and the cylinder coincide (see diagram).

Find, in terms of and , the distance of the centre of mass of the object from the base of the cylinder.
The point lies on the circumference of the base of the hemisphere. When the object is freely suspended from point , the base of the hemisphere makes an angle with the downward vertical through . It is given that . Find the value of .
The point is vertically below the point . One end of a light inextensible string is attached to , and the other end is attached to . A particle of mass is attached to the string so that the length is . The particle moves at a constant angular speed of in a horizontal circle with centre between and at a distance vertically below (see diagram). The string has length , and both sections of the string are taut. The tensions in the sections of the string and are and respectively. Find the value of and the value of .

A particle of mass moves along a straight horizontal line. At time , the speed of is and the distance of from its starting position is . The forces acting on are a constant driving force of magnitude and a resistive force of magnitude . Initially, is at rest.
Find the speed of when it has travelled .
Find an expression for in terms of .
A particle is moving on a fixed smooth horizontal surface with speed . The particle collides with a fixed smooth vertical barrier. Immediately before the collision, the direction of motion of makes an angle with the barrier, where . The kinetic energy of after the collision is times its kinetic energy before the collision.
Find the coefficient of restitution between and the barrier.
A second smooth vertical barrier is fixed to the surface and to the first barrier. The angle between the two barriers is . Particle subsequently collides with the second barrier and rebounds immediately after with speed at an angle with the second barrier. The coefficient of restitution is the same as in the first collision. Find the value of correct to 3 significant figures.
A particle of mass is attached to a fixed point by a light inextensible string of length . The particle initially hangs directly below at the point . The particle is then projected horizontally with speed , and begins to move in a vertical circle.
Find an expression for the tension in the string when it has turned through an angle . Give your answer in terms of , and .
Find, in terms of , the maximum height above the horizontal through that is reached by the particle.
A light elastic string has natural length and modulus of elasticity . One end of the string is attached to the fixed point , and the other end is attached to a particle of mass . The particle is held at and then released from rest so that it begins to fall vertically. In its subsequent motion, moves with velocity when the extension of the string is . The maximum extension of the string during this motion is .
Show that, for ,
Find the value of .
Find the maximum speed of .
The points and lie on a horizontal plane apart. The point lies at the foot of another plane which is inclined at an angle of above the horizontal such that . The point is on the inclined plane at a distance of from measured along a line of greatest slope. The points , and are in the same vertical plane and angle is obtuse. A particle is projected from at an angle to the horizontal with initial speed towards the inclined plane. The particle moves freely under gravity. The particle strikes the inclined plane at the point when its direction of motion is perpendicular to the inclined plane. Find, in either order, the value of and the value of .






