Physics A Level unit 4 questions

Hi, I'm stuck on a few physics questions on AQA unit 4, any help would be much appreciated.
1. A particle of mass 0.20kg moves with simple harmonic motion of amplitude 2.0x10^-2m. If the total energy of the particle is 4.0x10-5J, what is the time period of the motion?

2. Two pendulums, P and Q, are set up alongside each other. The period of P is 1.90s and the period of Q is 1.95s. How many oscillations are made by pendulum Q between two consecutive instants when P and Q move in phase with eachother?

3. Which of the following gives a correct unit for (g^2/G)?

- Nm^-2

- Nkg^-1

- Nm

- N

4. The gravitational field strength at the surface of the Earth is 6 times its value at the surface of the Moon. The mean density of the Moon is 0.6 times the mean density of the Earth. What is the value of the ratio (radius of Earth/radius of Moon)?

Reply 1

Cheesegrater4

i am doing these too!

i think i got 1. using KE=1/2mv^2 to find v which is max velocity. then put that into the v=wa to find w. then T=2pi/w to find T which i got as 2pi

i'm stuck on 2. and 3. 4. i got 1/3.6 probably wrong