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A car initially travelling with a speed of 10m/s accelerates at a rate of 5m/s every second for 4 seconds continuous to move with this speed for the next 6 second finally slows down at a rate 6m/s every second. a. How long will it take for the car stop motion? b. Draw V-t graph c. What is the acceleration of the car for each interval of time d. Draw a - t graph e. Calculate the total distance covered by the car f. How far does the car travel during the 4th and 12th second



User Dfeuer
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The total distance covered by the car is 80 + 180 + 75 = 335 meters.

How can you calculate the total distance covered by the car?

Initial speed (u) = 10 m/s

Acceleration (a) = 5 m/s²

Time (t) = 4 s

Final speed (v) = u + at = 10 + 5 * 4 = 30 m/s

Second Phase (Constant Speed):

Time (t) = 6 s

No change in speed, so final speed remains 30 m/s

Third Phase (Deceleration):

Initial speed (u) = 30 m/s

Deceleration (a) = -6 m/s² (negative for slowing down)

Time (t) is unknown. We need to find this.

Final speed (v) = 0 m/s (car stops)

Using the equation v = u + at, we can solve for t in the third phase:

0 = 30 - 6t

6t = 30

t = 5 seconds

Therefore, it takes the car 5 seconds to stop after decelerating.

b. V-t Graph:

The V-t graph is uploaded

Linearly increasing slope from 10 m/s to 30 m/s within 4 seconds (acceleration phase).

Horizontal line at 30 m/s for 6 seconds (constant speed phase).

Linearly decreasing slope from 30 m/s to 0 m/s within 5 seconds (deceleration phase).

c. Acceleration for Each Interval:

First Phase: 5 m/s² (acceleration)

Second Phase: 0 m/s² (constant speed, no acceleration)

Third Phase: -6 m/s² (deceleration)

d. a-t Graph:

The a-t graph is uploaded

Horizontal line at 5 m/s² (constant acceleration)

Horizontal line at 0 m/s² (constant speed, no acceleration)

Horizontal line at -6 m/s² (constant deceleration)

e. Total Distance Covered:

First Distance = u * t + 1/2 at² = 10 * 4 + 1/2 * 5 * 4² = 80 m

Second Distance = v * t = 30 * 6 = 180 m

Third Distance = v * t - 1/2 at² = 30 * 5 - 1/2 * 6 * 5² = 75 m

Therefore, the total distance covered by the car is 80 + 180 + 75 = 335 meters.

f. Distance Traveled in 4th and 12th Seconds:

4th Second: During the 4th second, the car covers a distance of v * t = 10 * 4 = 40 meters.

12th Second: During the 12th second, the car is already in the constant speed phase, so it covers a distance of v * t = 30 * 1 = 30 meters.

A car initially travelling with a speed of 10m/s accelerates at a rate of 5m/s every-example-1
User Phil Freeman
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