Answer:
Coefficient of kinetic friction = 0.146
Explanation:
Given:
Mass of sled (m) = 18 kg
Horizontal force (F) = 30 N
FInal speed (v) = 2 m/s
Distance (s) = 8.5 m
Find:
Coefficient of kinetic friction.
Computation:
Initial speed (u) = 0 m/s
v² - u² = 2as
2(8.5)a = 2² - 0²
a = 0.2352 m/s²
Nweton's law of :
F (net) = ma
30N - μf = 18 (0.2352)
30 - 4.2336 = μ(mg)
25.7664 = μ(18)(9.8)
μ = 0.146
Coefficient of kinetic friction = 0.146
The heat pump is a thermal machine that takes heat from a cold space and transfers it to a hotter one thanks to a work provided from the outside, that is, it does exactly the same as the refrigerating machine, the only thing that changes is the objective (In the refrigerating machine the objective is to cool and keep the cold space cold. The heat pump, however, aims to provide heat and keep the hot space warm)
Therefore the correct answer is A. <em>A heat pump uses work to transfer energy by heat from a colder environment to a warmer environment.</em>
The frequency of a tuning fork that takes2.50×10⁻³ s to complete one oscillation would be 400 Hz.
<h3>What is the frequency?</h3>
It can be defined as the number of cycles completed per second. It is represented in hertz and inversely proportional to the wavelength.
As given in the problem a tuning fork takes 2.50×10⁻³ s to complete one oscillation.
Frequency = 1/time period of the oscillation
Frequency of the tuning fork = 1/time period
=1/2.50×10⁻³
=400 Hz
Thus the frequency of a tuning fork comes out to be 400 Hz.
Learn more about frequency here, refer to the link;
brainly.com/question/14316711
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