Friction acts in a direction what to the directions of the objects motion

It takes 5.06 J of work to stretch a Hooke's-law spring 13.3 cm from its unstressed length. How much the extra work is required to stretch it an additional 13.4 cm? Answer in units of J. It takes 5.06 J of work to stretch a Hooke's-law spring 13.

The range of wavelengths for visible light is from 3.9*10^-7m. What is the corresponding range of frequencies for visible light

A child in a boat throws a 5.90-kg package out horizontally with a speed of 10.0 m/s. Calculate the velocity of the boat immediately after, assuming it was initially at rest. The mass of the child is 28.0 kg and that of the boat is 35.0 kg.

Balance the following equation Fe203+HCL fecl3+H20

The four terrestrial planets that have solid, rocky surfaces are A. Mars, Venus, Earth, and Jupiter. B. Mercury, Venus, Jupiter, and Mars. C. Mercury, Jupiter, Saturn, and Mars. D. Mercury, Venus, Earth, and Mars.

Heat that is transferred by the movement of currents within a fluid is called?

5. What is the percent composition of sulfur in H2SO4? A. 32.7% B. 65.2% C. 98.1% D. 2.1%

A 0.8kg object accelerate at a rate of4 m/s2. What is the net force acting on a object

Which of the following is the best definition of an isotope? A. elements of the same kind with different numbers of neutrons B. elements of the same kind that have lost electrons C. elements of the same kind that have different electrical charges

Two cars approach each other; both cars are moving westward, one at 85 km/h, the other at 54 km/h. what is the magnitude of the velocity of the first car relative to (in the frame of reference of) the second car? answer in units of km/h.