A construction worker with a weight of 850 N stands on a roof that is sloped at 20. What is the magnitude of the normal force of the roof on the worker?

A trumpeter is placed on a moving sidewalk that moves at a constant velocity of 4.5 m/s. A listener is standing 6.0 m in front of the trumpeter on the same sidewalk. The trumpeter plays a note of frequency 290 Hz.

The former soviet union launched the first artificial earth satellite. What is the name of this satelitte?

The general formula for an acid is

Magnetic fields go from the north poles of magnets to the south poles of magnets. true or false

In 1 km races, runner 1 on track 1 (with time 2 min, 28.13 s) appears to be faster than runner 2 on track 2 (2 min, 28.48 s). however, the length l2 of track 2 might be slightly greater than the length l1 of track 1.

Which of these rocks are formed by volcanic activity? select the two correct answers. a. marble b. basalt c. limestone d. granite e. sandstone

Which source is most likely an authority on the subject? Dr. Vale, a pediatrician, discusses electrical circuitry on her home-improvement website. Jonah, an amateur cook, teaches his son how to make the best grilled cheese sandwiches.

What methods can be used to break down substances into elements

8. A gas is contained in a horizontal piston-cylinder apparatus at a pressure of 350 kPa and a volume of 0.02 m3. Determine the work done by the piston on the gas if the cylinder volume is increased to 0.15 m3 through heating.

A 75.0 kg person stands on a scale in an elevator. (a) What does the scale read (in N and in kg) when the elevator is at rest?