Two children are holding onto opposite ends of a rope. The one on roller skates is being swung around in circles. If the moving child weighs 75 lb and he attains a constant speed of 12 ft/s, and if the rope is 10. ft long, how much tension is in the rope? Neglect friction.

The position of a dragonfly that is flying parallel to the ground is given as a function of time by r⃗ =[2.90m+(0.0900m/s2)t2]i^− (0.0150m/s3)t3j^. a: at what value of t does the velocity vector of the insect make an angle of 34.0 degree clockwise from the x-axis? b: at the time calculated in part (a), what is the magnitude of the acceleration vector of the insect? c : at the time calculated in part (a), what is the direction of the acceleration vector of the insect?

What is the temperature in degrees celsius of a substance with a tempature of 49k

At the negative terminal of the battery the electron has electric potential energy. what happens to this energy as the electron jumps from the negative to the positive terminal?