# 2012 waec physics theory questions and answers: 2012 waec physics expo:

waec 2012 physics questions and answers:

This is the continuation of the last physics questions and answers for waec 2012 i just posted.

waec 2012 free physics questions and answers, expo

Below are the questions and answers for waec 2012 physics. This are the waec 2012/2013 physics expo.

You are to choose five out of the first ten questions.
1.) A fruit from a tree of mass 2kg is 5m above the ground.
Calculate the Potential Energy of the fruit if it has fallen 3m from the tree.

2.) An object of mass 50kg is placed on aninclined plane at 30 degrees to the horizontal.
The height of the inclined plane is 250cm and its length is 500cm.
What work is done in moving the object down the plane?(Take g=10m/s).

3.)Draw a labelled diagram of a vacuum flask.
Explain how its construction minimizes heat with the surrounding.

4.) The length of a side of a metallic cube at20degrees centigrade is 5cm.
Given that the linear expansivity ofthe metal is 4*10^-5,
find the volume of the cube at 120 degrees centigrade.

4b.) Define the term”cubic expansivity”
5.) What is meant by a dielectric substance?
5b.) List the factors which determine the capacitance of a parallel plate capacitor andstate the effect each of them has on capacitance?

6.) Distinguish between stress and strain as used in elasticity.
6b.) When a force of 40N is applied to the free end of an elastic cord,an extension of 5cm is produced in the cord.
Calculate the work done on the cord.

7.) A stone is projected horizontally from the top of a tower with a speed of 5m/s.
It lands on the ground level at a horizontal distance of 20m from the foot of the tower.
Calculate the height of the tower(g=10m/s).

8.) Explain cations
8b.) Draw and label an electrolysis cell.

9.) A capacitor of capacitance 25micro-farad is connected to an a.c power source of 200Hz.
Calculate the reactance of the capacitor.

10.) A half-life of a radioactive source is 1 minute.
If the ratemeter connected to the source registers 200micro-ampere at a given time,
what would be its reading after 3 minutes?

This is the latest waec 2012 questions and answers for physics.