1. A child sits on a tire swing that is suspended by a single rope from a tree branch. What is the tension in the rope if the mass of the child and tire is 40 kg?
O a) 50 N
Ob) 40 N
Oc) 390 N
Od) 1600 N
O e) 4.1 N
2. A 310 kg spacecraft weighs 820 N on the surface of Planet Zphyz. What is the acceleration due to gravity on the

Under conditions for which the same room temperature is maintained by a heating or cooling system, it is not uncommon for a person to feel chilled in the winter but comfortable in the summer. provide a plausible explanation for this situation (with supporting calculations) by considering a room whose air temperature is maintained at 20â°c throughout the year, while the walls of the room are nominally at 27â°c and 14â°c in the summer and winter, respectively. the exposed surface of a person in the room may be assumed to be at a temperature of 32â°c throughout the year and to have an emissivity of 0.90. the coefficient associated with heat transfer by natural convection between the person and the room air is approximately 2 w/m2 â‹…â‹… k. what is the ratio of the thermal resistance due to convection to the thermal resistance due to radiation in the summer? what is the ratio of thermal resistances in the winter

Wavelength, frequency, and energy are related. what happens to a wave as it’s wavelength gets shorter?

What is the mass of the water that is being heated? it requires 2,500 joules to raise a certain amount of water (c = 4.186 jig c) from 20.0°c to 60.0°c. o 159 o 40 g o 63 g o 80 g