Before the driver applies the brakes ( with the reaction time ):
d 1 = v0 · t = 20 m/s · 0.53 s = 10.6 m
After that:
v = v0 - a · t1
0 = 20 m/s - 7 · t1
7 · t1 = 20
t1 = 2.86 s
d 2 = v 0 · t1 - a · t1² / 2
d 2 = 20 m/s · 2.86 s - 7 m/s² · (2.86 s)²/2 = 57.2 m - 28.6 m = 28.6 m
d = d 1 + d 2 = 10.6 m + 28.6 m = 39.2 m
Answer: the stopping distance of a car is 39.2 m.
The time taken by the rock will be 8.77 seconds.
<h3>What is speed?</h3>
Speed is defined as the ratio of the time distance traveled by the body to the time taken by the body to cover the distance.
Given that:-
The equation for free fall at the surface of some planet (s in meters, t in seconds) is s = 2.86t²
The time will be calculated by using the speed formula.
Speed = Distance \ Time
25.1 = 2.86t² \ t
t = 25.1 / 2.86
t = 8.77 seconds
Therefore the time taken by the rock will be 8.77 seconds.
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The greatest common factor of two numbers, one of which is 1, will always be 1.
Step-by-step explanation:
point slope formula: y-y1=m(x-x1)
m= y2-y1/x2-x1
input numbers
so slope:
m=(9--8)/(-7--8)
(-)×(-)=+
(+)×(-)=(-)
so m=17/1
m=17
now point slope
y--8=17(x--8)
y+8=17x+136
to get y alone we have to use opposite operations
y and 8 are adding so we need to subtract on both sides
y+8-8=17x+136-8
y=17x+128
The answer to this is B. y=-x-5.
