a 25 kg child is initially riding in a 50 kg cart moving at a speed of 2.0 m/s. the child manages to jump off the back of the cart in such a way that he has no final velocity. what is the resulting velocity of the cart? compare the child's change in momentum to the cart's change in momentum. what additional information would be needed in order to determine the force the child used to jump off the cart?​

Consider a 1000 w iron whose base plate is made of 0.5 cm thick aluminum alloy 2024-t6 (ρ = 2770 kg/m3 and cp = 875 j/kg°c). the base plate has a surface area of 0.03 m2. initially, the iron is in thermal equilibrium with the ambient air at 22°c. assuming 90% of the heat generated in the resistance wires is transferred to the plate, determine the minimum time needed for the plate temperature to reach 200°c.

Examples of states of consciousness include a. daydreaming b. dreaming during sleep c. hypnosis d. all of the above

A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.