A 0.20-kg baseball is thrown with a speed of 20 m / s. If the speed of the ball at the start of the throw is zero, calculate the net work during the throw.

Work out sian speed for the first 30 minutes of her journey. give your answer in km/h.

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?

Could we see a galaxy that is 20 billion light-years away?