A 50kg box is pulled on by a rope. The rope applies a horizontal force of 180 N to the box. What is the normal force exerted on the box by the floor?

The density of air on the Earth decreases almost linearly with height from 1.22kgm-3 at sea level to 0.74 kgm-3 at an altitude of 5000m. Atmospheric pressure at the Earth's surface on a particular day is 100000Pa.

A 55.0-g piece of copper wire is heated, and the temperature of the wire changes from 19.0°C to 86.0°C. The amount of heat absorbed is 343 cal. What is the specific heat of copper? Show your work.

A fisherman notices that one wave passes the bow of his anchored boat every 4 seconds. He measured the wavelength to be 8.5 meters. How fast are the waves traveling?

Demonstrate that plants use photosynthesis to grow throughout their lives

A record of travel along a straight path is as follows: 1. Start from rest with constant acceleration of 2.60 m/s2 for 11.0 s. 2. Maintain a constant velocity for the next 2.60 min. 3. Apply a constant negative acceleration of - 9.38 m/s2 for 3.

When viewing a piece of art that is behind glass, one often is affected by the light that is reflected off the front of the glass (called glare), which can make it difficult to see the art clearly.

force used to lift a 25kg mass to a height of 24m in 5 sec does 2120J of work. Calculate the power.

Which statement is true about the atom? A: it contains positive electrons, uncharged protons and negative protons. B: it contains uncharged neutrons, positive electrons and negative protons.

Steel objects can become temporary magnets because they are mainly composed of which element?

How long does it takes the sun to rotate the earth?