Answer:
Force that acted on the body was F = 13 N
Explanation:
If once accelerated, the body covers 60 meters in 6 seconds, then its velocity is 60/6 m/s = 10 m/s
When the force was acting (for 10 seconds) the object accelerated from rest (initial velocity vi = 0) to 10 m/s (its final velocity). therefore we can use the kinematic equation for the velocity in an accelerated motion given by:
which in our case becomes;
and we can solve for the acceleration as:
a = 10/10 m/s^2 = 1 m/s^2
Therefore the force acting on the body, based on Newton's 2nd Law expression: F = m * a is:
F = 13 kg * 1 m/s^2 = 13 N
Answer:
4.7 x 10³ rad / s
Explanation:
During the time light goes and comes back , one slot is replaced by next slot while rotating before the light source
Time taken by light to travel a distance of 2 x 500 m is
= (2 x 500) / 3 x 10⁸
= 3.333 x 10⁻⁶ s .
In this time period, two consecutive slots come before the source of light one after another by rotation. There are 400 slots so time taken to make one rotation
= 3.333 x 10⁻⁶ x 400
= 13.33 x 10⁻⁴ s
This is the time period so
T = 13.33 X 10⁻⁴
Angular speed
= 2π / T
= 
4.7 x 10³ rad / s
Answer:
the source of sound moves towards an observe
Explanation:
The Doppler effect is related to waves such as sound or light. the effect causes an increase or decrease in the frequency of sound light or other waves when the souces either move towards or away from the observer. For example the siren of the train to a person on the platform, the redshift seen by astronomers.
Therefore, The Doppler shift can be observed when the source of sound moves towards an observer From a place closer to the observer than the last wave's crest, each consecutive wave crest is sent. Each wave therefore, takes a little less time than the preceding wave to reach the observer.
In this item, we are asked to determine the speed of the bobsled given the distance traveled and the time it takes to cover the certain distance. This can mathematically be expressed as,
speed = distance / time
Substituting the given values in this item,
speed = (113 m) / (29 s)
speed = 3.90 m/s
<em>ANSWER: 3.90 m/s</em>
