Q1. A glass windowpane in a home is 0.620 cm thick and has dimensions of 0.93 m 1.90 m. On a certain day, temperature of the interior surface of the glass is 23.0 °C and the outdoor temperature is 0°C. Suppose the thermal conductivity of the glass is 0.80 W/m • °C.
What is the rate at which energy is transferred by heat through glass?
Q2. The wheels, axle, and handles of a wheelbarrow weigh W = 58 N. The load chamber and its contents weigh WL = 617 N. The drawing shows these two forces in two different wheelbarrow designs. To support the wheelbarrow in equilibrium, the man's hands apply a force to the handles that is directed vertically upward. Consider a rotational axis at point where the tire contacts the ground, directed vertical to the plane of the paper. Find out the magnitude of the man's force for both designs.