The sum of all forces acting on an objectbalance forcefrictionnet force

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?

Positive ions differ from neutral atoms in that

Which of the following examples illustrates static friction? a box sits stationary on a ramp. a ball rolling on the lawn eventually comes to rest. a car rounds a curve on a road. a fish swims upstream.