Do all protostars become stars?

Find the momentum of a 51kg object moving at a speed 5.21 m/s.

A child's first bycicle has 12 - inch tires. These tires have a 6-inch radious. How far does the bicycle move foward each time the wheel makes one complete rotation?

Why do clastic sedimentary rocks generally form underwater?

Why might city areas have a higher temperature than rural areas?

A 113 ‑turn circular coil of radius 2.71 cm and negligible resistance is immersed in a uniform magnetic field that is perpendicular to the plane of the coil. The coil is connected to a 10.3 Ω resistor to create a closed circuit.

Determine the total mechanical energy of a 250 g baseball if it has a velocity of 30 m/s when it leaves the pitcher's hand 1.2m above the ground.

When distances were carefully measured from Earth to globular clusters above and below the Milky Way plane (where our view of them is not obscured by interstellar dust and gas), their distribution was found to be

Imagine you transfer heat into a gas. This heat splits up in two different ways: Additional thermal energy making the gas hotter and "fuel" for the gas to do work. Let's suppose, 64% of the transferred heat transforms into thermal energy.

How much heat is absorbed by a 61g iron skillet when its temperature rises from 5oC to 29oC?

Explain the relationship between motion and frame of reference.