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A 60 kg student runs up a 300m long, 8.5° ramp at a constant speed of 2.5 m/s on a 25°C day. The student has a surface area of 1.50 m2, 34°C skin temperature, a skin emissivity of 0.90 and muscles that are 25% efficient. The surface transfer coefficient is 8 watts per square metre-degree. If resistance forces on the student amount to 54 N, then find a) the force required to run up the ramp b) the rate at which the student does work c) the rate at which heat energy is generated by the student (joules per second) d) the rate of heat radiation by the skin e) the rate of convective cooling f) the rate of sweating (kg/s) required to maintain constant body temperature given the rate of exercise, radiative emission, and convective heat losses.
a catapult at 45° to the horizontal. Your arrow should be
10 cm long, representing a velocity of 10 m s−1. Draw onto
your diagram the horizontal and vertical components that
would make up the overall velocity. Use a ruler to measure
the size of the horizontal and vertical components, and
convert these lengths into metres per second using the same
scaling.
(b) Find the horizontal and vertical velocity components for
this catapult stone by calculation, and compare with your
answers from part (a).
(b) how much work does the motor do in one revolution?
She observes that when she mounts the scale suddenly, the pointer of the scale first
oscillates back and forth a few times with a frequency of 2.4 Hz. [5]
(a) What value of the spring constant can she deduce from these data?
(b) If she then takes a child of 20 kg in her arms and again stands on the scale, what
will be the new frequency of oscillation of the pointer?
if a depth of liquid of 1.0meter causes pressure of 7 kpa,what is the specific gravity of the liquid
I need an ilustration and complete answer. Thank you
