# Physics Oxford & Cambridge University Interview Questions

**Past admissions interview questions for Physics**

A ball bearing is flying through space (vacuum and no overall gravitational field). It heads towards a doughnut, through it's centre and out the other side. Draw graphs of 1) speed versus time and 2) acceleration versus time. (submitted by Oxford applicant).

Draw the graphs of y=1/x +x and y=7+3cos(2x+pi/2). (submitted by Oxford applicant)

Describe a heat engine. (submitted by Oxford applicant)

An ant starts at one vertex of a solid cube with side of unity length. caculate the distance of hte shortest route the ant can take to the furthest vertex from the starting point. (answers in this book)

A telephone company has run a very long telephone cable all the way round the middle of the earth. Assuming the Earth to be a sphere, and without recourse to pen and paper, estimate how much additional cable would be required to raise the telephone cable to the top of the 10m tall telephone poles (answers in this book)

a thin hoop of diameter d is thrown on to an infinitely large chessboard with squares of side L. what is the chance of the hoop enclosing two colours? (answers in this book)

an infinitely large floor is tiles with regular hexagonal tiles of side L. Different colours of tiles are used so that no two tiles of the same colour touch. A hoop of diameter d i thrown onto the tiles. What is the chance of the hoop enclosing more than one colour? (answers in this book)

what is the volume of the largest cube that fits entirely within a sphere of unity volume? (answers in this book)

what is the area if an n-sided regular polygon inscribed within a circle of radius r? (answers in this book)

for a circle inscribed in inside a regular n-sided polygon, what is the minimum n so that the ratio of the area of part outside the circle to the area of the circle is less than or equals to 1/1000? (answers in this book)

give a vector proof that for a triangle inscribed within a semicircle, the included angle is always pi/2 (answers in this book)

Draw graph of weight versus time for the following: 1) man stands on scale very gently and then gets off again very gently; 2) man jumps onto scales and then jumps off again; 3) man stands on scale and lets his knees unlock so that he drops, then stops. For each of these describe the reasoning behind the graph. (submitted by Oxford applicant)

The wall of death fairground ride: it's spinning in a horizontal circle. Then the floor that people are standing on falls away. Calculate how fast it has to spin before the floor can fall away without the people dropping out given that : coefficient of friction=m and radius of the thing=r. (submitted by Oxford applicant)

Derive an expression for the separation of fringes caused by Young's Double Slit apparatus. (submitted by Oxford applicant)

Calculate (in algebraic terms) the change that will take place to the fringe pattern when a piece of glass is placed in front of one of the slits. Draw the new fringe pattern. (submitted by Oxford applicant)

Various questions about changing the speed of electrons and particle accelerators, e.g. why do particle accelerators have to be so large. How do they work? (submitted by Oxford applicant)

See a book called The Chicken from Minsk which has lots of great problems of the sort you need to be comfortable with. (submitted by Oxford tutor)

If you leave the fridge turned on in a thermally isolated room, what happens to the room? (The Independent)

Why can’t you light a candle in a spaceship? (molivam42's weblog)

How many grains of sand are there in the world? (molivam42's weblog)

What happens if I drop an ant? (molivam42's weblog)

Why can’t you light a candle in a spaceship (Oxford, Oxbridge Applications)

Why does fire go upwards (Oxford, Oxbridge Applications)

Does a cup of hot coffee cool quicker if milk is added before or after stirring? (Oxford, Oxbridge Applications)

What angle should you aim when trying to shoot a monkey that will fall out the tree the moment you shoot (Oxford, Oxbridge Applications)

What forces act on you were you at the centre of the earth? (Oxford, Oxbridge Applications)

Why could you not time a pendulum for 10000 swings by watching it with a timer? answer: you would get bored (Oxford, Oxbridge Applications)

**If you found these past interview questions useful, please remember to submit your questions, post interview, to oxbridgeinterview@gmail.com**