# Leaving Cert Applied Maths Higher Level 1976

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## Question 1

(a) Show that, if a particle is moving in a straight line with constant acceleration and initial speed , the distance travalled in time is given by .

(b) Two points and are a distance apart. A particle starts from and moves towards in a straight line with initial velocity and constant acceleration A second particle starts at the same time from and moves towards with initial velocity and constant deceleration . Find the time in terms of , at which the particle collide, and the condition satisfied by , , if this occurs before the second particle returns to .

## Question 2

A particle is projected upwards with a speed of m/s from a point on a plane inclined at to the horizontal. The plane of projection meets the inclined plane in a line of greatest slope and the angle of of projection, measured to the inclined plane, is .

(i) Write down the velocity of the particle and

(ii) its displacement from , in terms of and , after time seconds.

(iii) If the particle is moving horizontally when it strikes the plane at prove that and

(iv) calculate .

## Question 3

The diagram shows a light inelastic string, passing over a fixed pulley , connecting a particle of mass to a light movable pulley . Over this pulley passes a second light inelastic string to the ends of which are attached particles , of masses , respectively.

(i) Show in separate diagrams the forces acting on , and .

(ii) Write down the three equations of motion involving the tensions , in the strings, the acceleration of and the common acceleration of , *relative* to .

(iii) Show that .

## Question 4

A light smooth ring of mass is threaded on a smooth fixed vertical wire and is connected by a light inelastic string, passing over a fixed smooth peg at a distance from the write, to a particle of mass hanging freely. The system is released from rest when the string is horizontal. Explain why the conservation of energy can be applied to the system. If the ring descends a distance of while the particle rises through a distance

(i) show that

and

where , are the speeds of the ring and particle respectively.

Find when

(ii) and

(iii) when .

## Question 5

(a) State the laws governing the oblique collisions of elastic spheres.

(b) A sphere of mass moving with speed collides obliquely with a second smooth sphere at rest. The direction of motion of the moving sphere is inclined at to the line of centres at impact, and the coefficient of restitution is . After impact the directions of motion of the spheres are at right angles.

Find the mass of the second sphere in terms of , and the velocities of the two spheres after impact in terms of . Hence show that one quarter of the kinetic energy is lost.

## Question 6

Two uniform rods , of lengths , and of weights , respectively are smoothly hinged together at . They stand in equilibrium in a vertical plane with the end resting on rough horizontal ground and the end resting against a smooth vertical wall. The point is farther from the wall than and the rods , are inclined at angles , respectively to the horizontal where .

(i) Show in separate diagrams the forces acting on each rod.

(ii) By considering separately the equilibrium of the system and the rod , find the coefficient of friction at and

(iii) show that .

## Question 7

(a) Define simple harmonic motion.

(b) A particle of mass kg is attached to the ends of two light elastic strings, each of natural length m and elastic constant N/m. The other ends of the two strings are attached to two fixed points and in the same vertical line, where is m above . The particle when is released from rest from the midpoint of .

(i) By considering the forces acting on the particle when it is metres from , where , show that it is moving with simple harmonic motion.

(ii)Find the least time taken for the particle to reach the point , and find its speed there.

## Question 8

A pendulum of a clock consists of a thin uniform rod of mass and length to which is rigidly attached a uniform circular disc of mass and radius with the centre of the disc being at the point on where .

(i) Using the parallel axes theorem for the disc, show that the moment of inertia of the pendulum is free to oscillate in a vertical plane about such a fixed horizontal axis at .

(ii) It is released from rest with horizontal. Find the speed of when is vertical.

## Question 9

An atomic nucleus of mass is repelled from a fixed point by a force , where is the distance of the nucleus from and is a constant. It is projected directly towards with speed from a point where . Find the speed of the nucleus when it reaches the midpoint of and find how near it gets to .

## Question 10

(a) Using Taylor’s theorem find the first two terms in the Taylor series for in the neighbourhood of , i.e. the Maclaurin series for .

(b) State Archimedes principle for a body wholly or partly immersed in a liquid.

(c) A uniform thin rod is of length , of weight and specific gravity . The rod rests in equilibrium in an inclined position partly immersed in water with its lower end freely pivoted to a fixed point at depth below the surface of the water. Show in a diagram the forces acting on the rod and calculate the inclination of the rod to the vertical.

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### Citation:

State Examinations Commission (2018). *State Examination Commission*. Accessed at: https://www.examinations.ie/?l=en&mc=au&sc=ru

Malone, D and Murray, H. (2016). *Archive of Maths State Exams Papers*. Accessed at: http://archive.maths.nuim.ie/staff/dmalone/StateExamPapers/