What are the two factors that affect the friction force between two surfaces

What is the relationship between kelvin and Celsius

How do we determine the amount of dark matter in elliptical galaxies?

7. A 1300 kg car starts at rest and rolls down a hill from a height of 10.0 m. It then moves across a level (frictionless) surface and collides with a light spring-loaded guardrail with a spring constant k of 1.0 x 106 N/m.

Two people push on a boulder to try to move it. The mass of the boulder is 825 kg. One person pushes north with a force of 64 N. The other pushes west with a force of 38 N. Predict the magnitude of the acceleration of the boulder.

El Niño is actually good news for some parts of the world that experience a decreased chance of severe weather events. True False

How does a electron travel through a closed circuit?

Most people can detect frequencies as high as 20 000 Hz. Assuming the speed of sound in air is 345 m/s, determine the wavelength of the sound corresponding to this upper range of audible hearing.

Define absolute zero in terms of the kinetic energy of particles

Estimate the number of atoms in 1 cm^3 of a solid

How to find a vector from magnitude and direction?