- It takes 4200 Joules to heat up 1 kg of water by 1 C^o. If you have a kettle with a power of 2500 Watts, how long will it takes to boil 0.8 kg of water from an initial temperature of 25 C^o to the nearest second??
- what causes an object in friction with a surface to become negatively charged?
- Describe the forces acting on a skydiver over time, from the moment she jumps out of the plane until hitting the ground and the effect this has on her velocity. What happens when she opens her parachute?
- Explain the difference between a real and a virtual image.
- What is refraction?