Which statement is true about black dwarfs?

A. None currently exist in the universe.

B. They are very hot and massive.

C. They burn brightly for only a few weeks or months.

D. They form after supernova explosions ...?

A woman exerts a horizontal force of 4 pounds on a box as she pushes it up a ramp that is 10 feet long and inclined at an angle of 30 degrees above the horizontal. Find the work done on the box.

Mr. Roberts drives his car away from his house at a constant speed. Which of the following represents speed?

What is the energy of a photon with the wavelength 150 nm?

A rod 25 cm long moves in a plane perpendicular to a magnetic field of 600 G. The velocity of the rod is perpendicular to its length and the potential difference between the ends is 10 V. Find the speed of the rod.

Describe three clues that tell you that you are o serving a chemical change. Give an Example of each clues you described.

Who wrote the mayflower compact?

In the formula for specific heat, which quantity is measured in units of J/g•°C? a - c b - Q c - T d - m

The acceleration of an object is proportional to which of the following? the mass the energy of the object the inverse of the mass the inverse of the force applied

Suppose you squeeze a sponge into a small ball. does the mass of the sponge change? Does it's density change?

A solid round bar with diameter of 2-in has a groove cut to a diameter of 1.8-in, with a groove radius of 0.1-in. the bar is not rotating.