5 15 joules of work are done by forces other than gravity in taking an object from a position 3 m above the ground to a position 8 m above the ground What is the change in the gravitational potential energy of the object? A lt decreases by 5 joules B. It increases by 5 joules C. It increases by 11 joules. D. It increases by 15 joules​

Red light strikes a metal surface and electrons are ejected. if violet light is now used with a 10% greater intensity, what will happen to the ejection rate (number of ejected electrons per second) and the maximum energy of the electrons? a) greater ejection rate; same maximum energyb) same ejection rate; greater maximum energyc) greater ejection rate; greater maximum energyd) same ejection rate; same maximum energye) none of the above answers are correct