Answer:
Explanation:
Since the sled plus passenger moves with constant velocity , force applied will be equal to frictional force. Let the force applied be F
a ) Frictional force = μ R = F cosφ
R = mg - F sinφ
μ(mg - F sinφ) = F cosφ
μmg = F (μsinφ+cosφ)
F = μmg / (μsinφ+cosφ)
Work done
= F cosφ x d
= μmg x cosφ x d / (μsinφ+cosφ)
b )Work done
= 0.13 x 52.3 x 9.8 cos36.7 x 21.8 / ( 0.13 sin36.7 +cos36.7)
= 1164.61 / .87946
1324.23 J
c ) work done on the sled by friction
= - (work done by force)
= - μmg x cosφ x d / (μsinφ+cosφ)
d ) work done on the sled by friction
= - 1324.23 J
The method to choose depends on what information you have, and
on what you can measure. Here are a few possible methods:
-- Measure the period. Start your clock when one peak
of the wave passes you. Stop the clock when the next
peak passes you. The time between the two peaks is
the wave's period.
-- Divide the wave's wavelength by its speed. That quotient
is the wave's period.
-- Use an electronic frequency meter to measure the wave's
frequency. Then take its reciprocal (divide ' 1 ' by it). The
result is the wave's period.
You just use a bit of algebra. Kinetic energy is KE = (1/2) (mass) (speed squared). Multiply each side by (2/mass) and you have 2KE/mass=speed-squared. The square root of both sides then gives you the speed in terms of the kinetic energy.
