(a) The skater covers a distance of S=50 m in a time of t=12.1 s, so its average speed is the ratio between the distance covered and the time taken:
(b) The initial speed of the skater is
while the final speed is
and the time taken to accelerate to this velocity is t=2 s, so the acceleration of the skater is given by
(c) The initial speed of the skater is
while the final speed is
since she comes to a stop. The distance covered is S=8 m, so we can use the following relationship to find the acceleration of the skater:
from which we find
where the negative sign means it is a deceleration.
I wanna say its A . I could be wrong but im almost 100 percent sure that its A wood
In a longitudinal wave the particle displacement is parallel to the direction of wave propagation. ... The particles do not move down the tube with the wave; they simply oscillate back and forth about their individual equilibrium positions.Answer:
Explanation:
The time taken for the athlete to finish the race is 20 s (Option A)
<h3>What is power? </h3>
Power is simply defined as the rate at which work is done. It can be expressed mathematically as
Power (P) = work (W) / time (t)
But
Work = weight × distance
Therefore,
Power = (weight × distance ) / time
<h3>How to determine the time </h3>
- Mass (m) = 55 Kg
- Acceleration due to gravity (g) = 9.8 m/s²
- Weight = mg = 55 × 9.8 = 539 N
- Power (P) = 5.4 KW = 5.4 × 1000 = 5400 W
- Distance (d) = 200 m
- Time (t) =?
Power = (weight × distance ) / time
5400 = (539 × 200) / t
5400 = 107800 / t
Cross multiply
5400 × t = 107800
Divide both side by 5400
t = 107800 / 5400
t = 20 s
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Answer:
The object will travel 675 m during that time.
Explanation:
A body moves with constant acceleration motion or uniformly accelerated rectilinear motion (u.a.r.m) when the path is a straight line, but the velocity is not necessarily constant because there is an acceleration.
In other words, a body performs a u.a.r.m when its path is a straight line and its acceleration is constant. This implies that the speed increases or decreases uniformly.
In this case, the position is calculated using the expression:
x = xo + vo*t + ½*a*t²
where:
- x0 is the initial position.
- v0 is the initial velocity.
- a is the acceleration.
- t is the time interval in which the motion is studied.
In this case:
- x0= 0
- v0= 0 because the object is initially stationary
- a= 6
- t= 15 s
Replacing:
x= 0 + 0*15 s + ½*6 *(15s)²
Solving:
x=½*6 *(15s)²
x=½*6 *225 s²
x= 675 m
<u><em>
The object will travel 675 m during that time.</em></u>
