1. Please find the torque about a rod that is rotating about its center. The rod has been accelerated from 90 to 10000rpm in 15 seconds. The rod's mass is 0.6kg, and
its length is 0.5m.

Why is alternating current more effective at long–distance travel than direct current? a. the power lines are made out of conductors. b. transformers increase or decrease voltage as needed. c. the ac generator is more efficient. d. ac has lower voltage than dc.

How much work is done lifting a 9.10 kg box straight up onto a shelf that is 1.80 m high?

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?