Answer:
192000 J or 192 kJ
Explanation:
Work done = Force × distance moved along the direction of force.
From the question,
W = F×d............... Equation 1
Where W = work done by the car, F = Force of the car, d = distance move by the car along the direction of the force.
We can calculate for d using the equation of motion
d = (v+u)t/2..................... Equation 2
Where v = Final velocity of the car, u = Initial velocity of the car, t = time.
Given: u = 12 m/s, v = 0 m/s(skids to a stop), t = 4.0 s
Substitute into equation 2
d = (12+0)4/2
d = 24 m.
Also given: F = 8000 N
Substitute into equation 1
W = 8000×24
W = 192000 J
W = 192 kJ.
Answer:
Decreases
Explanation:
Force= mass * acceleration
If the mass increases but force stays the same then the acceleration would have to decrease to maintain the same force
The rectilinear motion is given as:
s = s0 + v0 t + (1/2) a t^2
We can see that the variables stand for:
s = final distance
s0 = initial distance
v0 = initial velocity
t = time
a = acceleration
<span>We can see that all these variable are always constant
EXCEPT acceleration. The rectilinear motion can only be applied if and only if
acceleration is CONSTANT.</span>
Answer:
10.87 m
Explanation:
Total length of the wire = 25 m
Let the length of one piece is y and other piece is 25 - y
Let the side of square is a.
So, 4 a = y
a = y / 4
And the side of triangle is b
3 b = (25 - y)
b = (25 - y) / 3
Area of square, A1 = side x side =
A1 = y² / 16
Area of equilateral triangle, A2 = 
Total area, A = A1 + A2
For maxima and minima, fins dA /dy
It is equal to zero.
9y = 173.2 -6.928 y
15.928 y = 173.2
y = 10.87 m
So, the length of wire to make square is 10.87 m.
This is true because of erosion. The harder the waves hit causes the roock to split and eventually break off.
