If an object is released in the shaft at the earth's surface, what speed will it have when it reaches the center of the earth?

Ineed asap! list 3 examples in which friction us or makes things easier in our daily life. explain the effect of friction for each. *make sure you explain the effect of friction for each example! *

5g of ammonium nitrate was dissolved in 60g of water in an insulated container. the temperature at the start of the reaction was 23.0°c and at the end it was 19.0°c. calculate the energy absorbed by the reaction.

Amachinist turns the power on to a grinding wheel, at rest, at time t = 0 s. the wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 96 rad/s. the wheel is run at that angular velocity for 40 s and then power is shut off. the wheel slows down uniformly at 1.5 rad/s2 until the wheel stops. in this situation, the time interval of deceleration is closest to: