A bike is travelling at a velocity of 7 m/s. The cyclist brakes for 2 seconds when a dog runs out in front of her. The bikes new velocity is 4m/s. Calculate the acceleration of the bike
-1.5
trust me on this one :)
V = Vo + a*T
4 = 7 + a*2
a = -3/2 = -1.5 m/s^2.
Well, it looks like the bike had to "paws" for a moment when the dog ran out in front of it. Let's calculate the acceleration.
First, we need to find the change in velocity. The initial velocity was 7 m/s, and the new velocity is 4 m/s.
Change in velocity = final velocity - initial velocity
Change in velocity = 4 m/s - 7 m/s
Change in velocity = -3 m/s
Now, we have the change in velocity and the time over which this change occurred, which is 2 seconds. The acceleration can be calculated using the following formula:
Acceleration = change in velocity / time
Substituting the values:
Acceleration = -3 m/s / 2 s
Acceleration = -1.5 m/s²
So, the acceleration of the bike is -1.5 m/s². The negative sign indicates that the bike is decelerating. Guess the bike had to put on the brakes quickly to avoid a "ruff" collision with the dog!
To calculate the acceleration of the bike, you need to use the following formula:
Acceleration = (Final Velocity - Initial Velocity) / Time
In this case, the initial velocity is 7 m/s, the final velocity is 4 m/s, and the time is 2 seconds.
Plugging these values into the formula, you get:
Acceleration = (4 m/s - 7 m/s) / 2 s = -3 m/s²
Therefore, the acceleration of the bike is -3 m/s². Note that the negative sign indicates that the bike is decelerating or slowing down.
For an acceleration of a
v(t) = at + c
initial velocity = 7 m/s
7 = a(0) + c
so v(t) = at + 7
when t = 2, v(2) = 4
4 = 2a + 7
2a = -3
a = -3/2
The bike decelerated at 3/2 m/s^2 or it accelerated at -3/2 m/s^2
Acceleration=Δv/Δt=(final velocity-initial velocity)/time taken
Initial velocity =7m/s
Final velocity=4m/s
Time=2sec
It would decelerate