A 650 N student is Rollerblading at a velocity of 7.8 m/s [W] when the student trips and slides horizontally along the trail, coming to a stop 0.95s.
Determine the students average acceleration
a = (v-Vo)/t.
a = (0-7.8) / 0.95 = -8.21 m/s^2.
To determine the student's average acceleration, we can use the equation of motion:
v = u + at
where:
v = final velocity (0 m/s, since the student comes to a stop)
u = initial velocity (7.8 m/s [W])
t = time (0.95 s)
First, let's rearrange the equation to isolate the acceleration (a):
a = (v - u) / t
Substituting the given values:
a = (0 m/s - 7.8 m/s [W]) / 0.95 s
To simplify the velocity calculation, we need to convert the direction to a vector notation. The given direction is "west" or "W." In vector notation, west is represented by a negative sign ("-"). Hence, the initial velocity becomes -7.8 m/s.
a = (0 m/s - (-7.8 m/s)) / 0.95 s
= 7.8 m/s / 0.95 s
≈ 8.21 m/s²
Therefore, the student's average acceleration is approximately 8.21 m/s².
To determine the student's average acceleration, we can use the formula:
Average acceleration = Change in velocity / Time taken
First, let's find the change in velocity. The student starts with a velocity of 7.8 m/s [W] and comes to a stop, so the final velocity is 0 m/s. The change in velocity is:
Change in velocity = Final velocity - Initial velocity
Change in velocity = 0 m/s - 7.8 m/s
Change in velocity = -7.8 m/s
Next, we need to determine the time taken. The question states that the student comes to a stop in 0.95s.
Now we can calculate the average acceleration:
Average acceleration = (-7.8 m/s) / (0.95 s)
Average acceleration = -8.21 m/s^2
Therefore, the student's average acceleration is approximately -8.21 m/s^2. Note that the negative sign indicates that the acceleration is in the opposite direction of the initial velocity.