Answer:
Well I'm going to go with A.
Explanation:
As per the question the mass of the boy is 40 kg.
The boy sits on a chair.
We are asked to calculate the force exerted by the boy on the chair at sea level.
The force exerted by boy on the chair while sitting on it is nothing else except the force of gravity of earth i.e the weight of the body .The direction of that force is vertically downward.
At sea level the acceleration due to gravity g = 9.8 m/s^2
Therefore, the weight of the boy [m is the mass of the body]
we have m = 40 kg.
Therefore, w = 40 kg ×9.8 m/s^2
=392 N kg m/s^2
= 392 N
392 is not an option but I'm guessing you can round down 2 .to option A. 390...?
Answer:
(A) Time period T = 6.28 SEC
(B) At highest point fore is - 575.83 N
(B) At lowest point force is 1050.97 N
Explanation:
We have given that mass m = 83 kg
Radius r = 13 m
Speed v = 6.10 m/sec
(A) Time period of the motion is given by
(b) Net force is given by
Force due to gravity
At highest point
(B) At lowest point
The frequency of the radio waves from the fm station is:
And the speed of the waves corresponds to the speed of light:
Therefore, the wavelength of the radio waves can be found by using the following equation:
The sign associated with the average velocity of the object is negative.
<h3>
Average velocity of the object</h3>
The average velocity of the object is calculated as follows;
Average velocity = (v1 + v2)/2
v1 = -20/30 = -0.667 m/s
v2 = 20/50 = 0.4 m/s
Average velocity = (-0.667 + 0.4)/2
Average velocity = -0.134 m/s
Thus, the sign associated with the average velocity of the object is negative.
Learn more about average velocity here: brainly.com/question/6504879
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