Q1. What temperature change would reason a 0.20 % enhance in the volume of a quantity of water that was at first at 20 ^circ {rm C}?
Q2. The focal point of a lens is the location of an image of a point of object at infinity." Discuss the notion of infinity in real terms as it applies to object distances. Based on this statement, can you think of a simple method for determining the focal length of a converging lens?
Q3. A ceiling fan with 80-{rm cm}-diameter blades are turning at 70 rpm. Assume the fan coasts to a stop 29 s after being turned off.