The density of a block of wood with a mass of 100 grams and a volume of 50 cubic centimeters is A. 2 g/cm3 B. 5,000 g/cm3 C. 500 g/cm3 D. 0.5 g/cm3

A box with a mass of 2 kg accelerates in a straight line from 4 m/s to 8 m/s due to the application of a force whose duration is 0.5 s. Find the average strength of this force.

To lift a load of 100 kg a distance of 1 m an effort of 25 kg must be applied over an inclined plane of length 4 m. What must be done to lift the load 2 m, using the same effort? A) Use an inclined plane of length 8 m.

Describe the earths formation from a nebula

What best describes why kepler's observation of planetary motion is a law instead of a theory

8. When a 100 N bag of nails hangs motionless from a single vertical strand of rope, how many newtons of tension are exerted in the strand? - What if the bag is supported by four vertical strands?

How does the strong nuclear force compare with the electrostatic force in the nucleus of an atom? A. The strong nuclear force is stronger and is only attractive. B. The strong nuclear force is weaker and acts over longer distances. C.

A 1100 - kg car collides with a 1300 - kg car that was initially at rest at the origin of an x-y coordinate system. After the collision, the lighter car moves at 20.0 km/h in a direction of 30 o with respect to the positive x axis.

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

A light plane must reach a speed of 33m/s for takeoff. how long a runway is needed if the the acceleration is 3.0m/s^2

How do astronomers learn about the internal structure and evolution of stars? How does a new star form? What causes a supernova to occur? Explain. Is the lifetime of a massive star shorter or longer than a star like the Sun? Why?