Answer:
a) During the reaction time, the car travels 21 m
b) After applying the brake, the car travels 48 m before coming to stop
Explanation:
The equation for the position of a straight movement with variable speed is as follows:
x = x0 + v0 t + 1/2 a t²
where
x: position at time t
v0: initial speed
a: acceleration
t: time
When the speed is constant (as before applying the brake), the equation would be:
x = x0 + v t
a)Before applying the brake, the car travels at constant speed. In 0.80 s the car will travel:
x = 0m + 26 m/s * 0.80 s = <u>21 m </u>
b) After applying the brake, the car has an acceleration of -7.0 m/s². Using the equation for velocity, we can calculate how much time it takes the car to stop (v = 0):
v = v0 + a* t
0 = 26 m/s + (-7.0 m/s²) * t
-26 m/s / - 7.0 m/s² = t
t = 3.7 s
With this time, we can calculate how far the car traveled during the deacceleration.
x = x0 +v0 t + 1/2 a t²
x = 0m + 26 m/s * 3.7 s - 1/2 * 7.0m/s² * (3.7 s)² = <u>48 m</u>
Answer:
work = 1275.3 J
Explanation:
work = (force)(distance)cosø ------- force = ma
=(mass*acceleration)(distance)cosø
=(20*9.81)(6.5)cos0
=1275.3J
nite that the angle of cosine is the difference between the angle of force and the distance. in this case, the force and the distance are in the same direction. :)
.75(m/s)^2
Use this picture
If you know the two on the bottom you multiply them but if you only know the top and one on the bottom you divide
Answer:
speed
Explanation:
its the speed
because the formula for deriving speed is distance/time
the unit for distance is metre
the unit for time is seconds
so speed is metre/seconds
so speed us m/s.
