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Two car (A) and (B) start from the rest at the same instant of time t=0 . From the points M and N respectively in uniformly accelerated rectilinear motion and in opposite directions as shownin the adjacent figure give acceleration of (A) is 4m/s² and that (B) is 2m/s² .MN 30km At the instant t the car (A) covered a distance d¹ and B covers a distance d² 1 determine as a function of t d¹and d² . 2 deduce the time meeting 2 cars . 3 answer the preceding questions but consider that car (B) in uniform rectilinear motion with a speed of 10 m/s​

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To solve the problem, let's break it down into three parts:

1. Determining the distance covered by cars A and B as a function of time:

For uniformly accelerated rectilinear motion, we can use the following equation to calculate the distance covered:

distance = initial velocity * time + (1/2) * acceleration * time^2

For car A:

The initial velocity is 0 m/s, and the acceleration is 4 m/s².

So, the distance covered by car A at time t is:

d¹(t) = 0.5 * 4 * t^2 = 2t^2

For car B:

The initial velocity is 0 m/s, and the acceleration is -2 m/s² (opposite direction to car A).

So, the distance covered by car B at time t is:

d²(t) = 0.5 * -2 * t^2 = -t^2

2. Deducing the time of meeting for the two cars:

To find the time of meeting, we need to set the distances covered by both cars equal to each other:

2t^2 = -t^2

Simplifying the equation:

2t^2 + t^2 = 0

3t^2 = 0

Since the equation equals zero, the only solution is t = 0. This means that the two cars meet at the starting point at t = 0.

3. Considering car B in uniform rectilinear motion with a speed of 10 m/s:

If car B is moving at a constant speed of 10 m/s, it means its acceleration is 0 m/s². Therefore, the equation for car B's distance covered becomes:

d²(t) = initial velocity * time = 10 * t = 10t

Now, we can answer the preceding questions using this new equation for car B.

1. The distance covered by car A at time t is still d¹(t) = 2t^2.

The distance covered by car B at time t is now d²(t) = 10t.

2. The time of meeting for the two cars can be found by setting the distances equal to each other:

2t^2 = 10t

Simplifying the equation:

2t^2 - 10t = 0

2t(t - 5) = 0

From this equation, we have two solutions:

t = 0 (the initial meeting point)

t = 5 seconds (when the two cars meet again after 5 seconds)

Therefore, the cars meet again after 5 seconds.

Please note that the distances calculated above are in terms of t, the time elapsed since t = 0.


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