I would say A not 100℅ thou
T=s/v=>t=1500/1,5=1000s
1,5km=1500m
Unequal opposite forces.
(They're unbalanced.)
Answer:
a) 
b) 
º
c) 
Explanation:
From the exercise we know that the collision between Daniel and Rebecca is elastic which means they do not stick together
So, If we analyze the collision we got
To simplify the problem, lets name D for Daniel and R for Rebecca
a) 
Since Daniel's initial velocity is 0
Now, lets analyze the movement in the vertical direction
Since 
Now, we can find the magnitude of Daniel's velocity after de collision
b) To know whats the direction of Daniel's velocity we need to solve the arctan of the angle
º
c) The change in the total kinetic energy is:
ΔK=
ΔK=![\frac{1}{2}[(45kg)(8m/s)^2+(70kg)(7.32m/s)^2-(45kg)(14m/s)^2]=-1094.62J](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%5B%2845kg%29%288m%2Fs%29%5E2%2B%2870kg%29%287.32m%2Fs%29%5E2-%2845kg%29%2814m%2Fs%29%5E2%5D%3D-1094.62J)
That means that the kinetic energy decreases
The magnitude of the displacement of the car from the starting point to halfway around the track is 256 m.
Answer:
Explanation:
Since the race track is a circular track, the distance for one lap will be equal to the circumference of the circular track. And the circumference will be equal to the circumference of the circle.
Since the radius of the track is given as 200 m, then the circumference of the circular track will be
Circumference = 2πr = 2 × 3.14 × 200
So the circumference of the circular track = 1256 m.
So the starting point or position of the track is considered as zero and if the car has traveled half way means, the car has covered half of the circumference of the track.
As the circumference = 1256 m, then half of the circumference of the circle = 1256/2 = 256 m.
So the displacement is the measure of difference between the final position and initial position. As here the initial position is zero and the final position is the halfway around the track which is equal to 256 m.
Then Displacement = Final-Initial = 256-0= 256 m.
So the magnitude of the displacement of the car from the starting point to halfway around the track is 256 m.
