Answer:
Kinetic energy, KE = 45 J
Explanation:
It is given that,
Force applied by girl on a sled, F = 15 N
It moves a distance, d = 3 m
We need to find the kinetic energy of the sled after she pulls it. We know that the work done is equal to the change in kinetic energy
(initial at rest)
So, the kinetic energy of the sled after she pulls it is 45 J. Hence, this is the required solution.
Answer:
Wavelength,
Explanation:
It is given that,
Speed of radio waves is
Frequency of radio waves is f = 101,700,000 Hz
We need to find the wavelength of WFNX’s radio waves. The relation between wavelength, frequency and speed of a wave is given by :
is wavelength
So, the wavelength of WFNX’s radio waves is 2.94 m.
Answer:
v_average = 15 m / s
Explanation:
The average speed can be found in two ways,
* taking the distance traveled and divide it by the time spent
* taking the velocities in each time interval and then finding the weighted average by the time fraction
v_average = 1 / t_total ∑ vi ti
Let's apply this last equation
Total time is
t = t₁ + t₂
t = 10 + 10 = 20 min
v_average = 10/20 10 + 10/20 20
v_average = 10/2 + 20/2
v_average = 15 m / s
Answer:
Explanation:
We could use the following suvat equation:
where
s is the vertical displacement of the coin
v is its final velocity, when it hits the water
t is the time
g is the acceleration of gravity
Taking upward as positive direction, in this problem we have:
s = -1.2 m
And the coin reaches the water when
t = 1.3 s
Substituting these data, we can find v:
where the negative sign means the direction is downward.