How much force required to prevent a book from falling if the mass of the book is 50 grams?

What do radio waves and microwaves have in common? both are at the side of the spectrum that has the shortest wavelengths. both are at the side of the spectrum that has the lowest radiant energy. both are at the side of the spectrum that has the lowest frequency. both are found next to visible light on the electromagnetic spectrum.

Aforklift raises a 1,020 n crate 3.50 m up to a shelf. how much work is done by the forklift on the crate? the forklift does j of work on the crate.

What are the similarities & differences between a thermistor and a light dependent resistor in physics?