6. one of the most powerful forklifts was built in sweden in 1991. the lift is
capable of lifting a 9.0 x 104 kg mass a distance of 2.0 m above the ground. if
the work done by the forklift on the mass is 1.8 x 10° j, what is the force that
the lift exerts on the mass?

What is the conversion factor between kg/m^3 and g/m^3. express your experimental values for the densities in kg/m^3.

One day, after pulling down your window shade, you notice that sunlight is passing through a pinhole in the shade and making a small patch of light on the far wall. you see that the patch of light seems to be a circular diffraction pattern. it appears that the central maximum is about 1 cm across and you estimate that the distance from the window shade to the wall is about 3 m. what is (a) the average wavelength of sunlight? (b) the diameter of the pinhole?

A100-watt light bulb illuminates a solar cell. the electricity from the solar cell operates a water pump that delivers 1 watt of power. what is the efficiency of the system?