Question
1. A runner is running on a circular track that is 200 m in circumference. Find out the magnitude of his acceleration in m/s2 when he is running at a constant speed of 8.0 m/s.
2. A 529 kg automobile slides across an icy street at a speed of 66.0 km/h and collides with a parked car that has a mass of 856 kg. The two cars lock up and slide together. What is the speed of two cars just after they collide?
3. A ball with mass 3.5 kg is thrown horizontally with a velocity of 6.9 m/s at a cart of mass 21.3 kg. The ball bounces back with a velocity of -2.971 m/s. The collision is not elastic. Friction between cart and road surface can be neglected. What is the final velocity of the cart?
4. A 230 kg satellite is orbiting on a circular orbit 6870 km above the Earth's surface. Find out the speed of the satellite. (The mass of the Earth is 5.98×1024 kg, and radius of the Earth is 6370 km.)
5. A mechanic can exert the most force of 26 N. He has a wrench of length 0.8 m. What is the greatest torque he can concern to a bolt using that wrench?