Answer:
b) there must be a component of force parallel to the motion of the object.
Explanation:
We know that work done on a body by an external force is calculated by the formula given below:
W = F.d = Fd Cos θ
where,
W = Work Done by the force on the body
F = Magnitude of force
d = displacement of the body
θ = The angle between the direction of motion of the body and the force applied
It is clear from the formula of the work done, that "F Cosθ" represents the component of the force, that is acting in the direction of motion of the object or parallel to the direction of motion of the object. So, if there is no component of force parallel to motion of object, then this factor will become zero. As a result, the work done will also be zero.
Therefore, the correct option will be:
b) <u>there must be a component of force parallel to the motion of object.</u>
Explanation:
We will assume that the rim of the wheel is also very thin, like the spokes. The distance <em>s</em><em> </em><em> </em>between the spokes along the rim is
The 20-cm arrow, traveling at 6 m/s, will travel its length in
The fastest speed that the wheel can spin without clipping the arrow is
The angular velocity 
of the wheel is given by
In terms of rev/s, we can convert the answer above as follows:
As you probably noticed, I did the calculations based on the assumption that I'm aiming for the edge of the wheel because this is the part of the wheel where a point travels a longer linear distance compared to ones closer to the axle, thus giving the arrow a better chance to pass through the wheel without getting clipped by the spokes. If you aim closer to the axle, then the wheel needs to spin slower to allow the arrow to get through without hitting the spokes.
Answer:
A sound wave that has a higher frequency is a wave that makes 12 cycles per second.
Explanation:
The frequency of a wave is the same as the frequency of the vibrations that caused the wave. This takes more energy, so a higher-frequency wave has more energy than a lower-frequency wave with the same amplitude.
