4. A 20 g lead bullet (initially at 2000(3) is red at 500 m/ s into :1 200 g block of aluminum (initially at 25C) which is sitting just in front of the bottom of a 20 incline. The bullet is stuck into the block upon hitting it1 and the block then slides 18m up the incline before friction brings the block to rest. {a} How fast is the block moving just after bullet hits it? (b) 1What is the temperature of the fused hulletfhloek when it eomes to a stop? 2. The two masses below are connected by a taut string passing over a lightweight fric- tionless pulley. The contact between the masses and the surface they rest on has a coefficient of kinetic friction of 0.2. (a) Determine the magnitude of the acceleration of the system. 1 kg 20 609 2 kg (b) Assuming the masses begin at rest and travel a distance of 1.2 m, find the average power due to the tension force on the 2 kg mass