When the body is at rest, its speed is zero, and the graph lies on the x-axis.
When the body is in uniform motion, the speed is constant, and the graph is a horizontal line, parallel to the x-axis and some distance above it.
It's impossible to tell, based on the given information, how these two parts of the
graph are connected. There must be some sloping (accelerated) portion of the graph
that joins the two sections, but it cannot be accounted for in either the statement
that the body is at rest or that it is in uniform motion, since acceleration ... that is,
any change of speed or direction ... is not 'uniform' motion'.
Answer:
a. 
b. 
must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c. 
is the time taken to stop after braking
Explanation:
Given:
- speed of leading car,
- speed of lagging car,
- distance between the cars,
- deceleration of the leading car after braking,
a.
Time taken by the car to stop:
where:
, final velocity after braking
time taken
b.
using the eq. of motion for the given condition:
where:
final velocity of the chasing car after braking = 0
acceleration of the chasing car after braking
must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c.
time taken by the chasing car to stop:
is the time taken to stop after braking
Answer:
Standard deviation = 3
Explanation:
Given
Required
Determine the standard deviation
First, we need to determine the variance;
This gives:
Know that:
Where SD represents standard deviation
This gives
Take square root
Answer:
20 V
Explanation:
Power is 100 J/s or 100 W.
We know that P = IV = 
.
Isolate the potential difference. V = 
= 
= 20 V
