085-1263404

### My Journal

All things Mathematical
5Oct2018
##### Question 1

A liner proceeding on a course North of East appears to be moving N.E. as seen from a tug moving at knots in an easterly direction. Find the speed of the liner.

How much must the tug increase its speed so that the liner will now appear to be moving due North?

##### Question 2

A piece of uniform wire is bent so as to form three sides , , of a square . Find the position of the centre of gravity.

If a particle of mass equal to that of the wire is attached at the point , and the whole is freely suspended at , find the inclination of to the vertical.

##### Question 3

An engine pulls a train at a uniform speed of miles per hour up an incline of of . If the couplings between the train and the engine break, how far will the train continue to run up the incline, if the resistance to its motion is lb. wt. per ton?

##### Question 4

A football is kicked from a spot on the ground with a velocity of feet per second and strikes a vertical wall feet away at a point feet above the ground. Find the two possible angles of projection. Using the same initial velocity, what angle of projection will give the greatest height up the wall?

##### Question 5

A body of mass lb. is resting on a rough plane inclined to the horizontal at an angle , the coefficient of friction being . Find an expression for the force acting along the line of greatest slope which will just drag the body up the plane.

Find also an expression for the least force required (when applied in the most suitable direction) to drag the body up the plane, and find the value of this force when , , .

##### Question 6

Two masses of and lb. are connected by a light inextensible string of length ft. Both masses rest on a smooth horizontal table, the lb. mass being one foot from the edge of the table and from the lb. mass which is resting at the edge. If the lb. mass is pushed gently over the edge, find the speed of lb. mass (i) when it is jerked into motion, and (ii) when it reaches the edge of the table.

##### Question 7

A triangular lamina is immersed in a vertical position in water with its vertex at the surface and its base parallel to the surface. If inches and the height of the triangle is equal to inches, find the thrust on due to the water. If , are the middle points of , , respectively, compare the total thrusts on and .

In what ratio must a parallel to cut the other sides of the triangle so that the thrusts on the two portions of triangles may be equal?

[ cubic ft. of water  lbs.]

##### Question 8

A mass of lb. fastened to a string ft. long revolves as a conical pendulum, the mass moving in a horizontal circle with a speed of feet per second. Find the tension of the string and its inclination to the vertical.

##### Question 9

What is Simple Harmonic Motion? What is meant by the period, amplitude, and frequency of a S.H.M.?

A particle is moving in S.H.M. of period seconds and amplitude cm. Find the displacement, speed an acceleration of the particle second after it reaches its maximum positive displacement.

##### 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/

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