Given: Please see the attached image below.
To be able to
subtract vectors, we can either use the parallelogram method or the triangle
method. Take note that the only difference is that alternatively adding vectors
A and B, we will instead be adding A and – B. When we ponder of vector subtraction, we must
anticipate about it in terms of adding a negative vector. A negative vector has the same magnitude as the
original vector, however, it has an opposite direction.
So in this problem, the two vectors that will have the
largest magnitude are A & F when subtracted (i.e., when one vector is
subtracted from the other).
It moves backwards do to the impact. this is because force can not be created nor destroyed so it is transferred.<span />
Answer:
4.17 m/s²
Explanation:
We are told the reaction time is 0.2 s. Now, during this reaction time the car is going to travel an additional distance of
: x = u × t = 40 × 0.2 = 8 m
where u is the initial velocity of the car which is 40.0 m/s.
We are told that he had 200 m to stop before applying brakes. Thus, after applying brakes, he now has a distance to cover of; s = 200 - 8 = 192 m
Since vehicle is coming to rest acceleration would be negative, thus using Newton's equation of motion, we have;
v
² = u² - 2as
v = 0 m/s since it's coming to rest
u = 40 m/s
s = 192 m
Thus;
0² = 40² - 2(a)(192)
0² = 1600 - 384a
a = 1600/384
a = 4.17 m/s²
Speed =distance/time
3.25=3.00/time
3.25xt=3.00
t=3/3.25
s=0.9s
