What is the work done by gravity if a 50kg block is pushed along a 40m track? (g=10)
a) OJ
b) 5J
c) 3)
d) 10J
e) 15)

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?

If a spring has a k value of 100 newtons per meter and it is stretched 0.50 meters, what is the restoring force of the spring?

In positive numbers less than 1, the zeros between the decimal point and a non-zero number are blank significant