Answer:
The sum of PE and KE remains constant
Explanation:
Answer:
18.9 m.
Explanation:
From the question given above, the following data were obtained:
Initial velocity (u) = 0 m/s
Final velocity (v) = 70 km/h
Height (h) =?
Next, we shall convert 70 km/h to m/s. This can be obtained as follow:
3.6 km/h = 1 m/s
Therefore,
70 km/h = 70 km/h × 1 m/s / 3.6 km/h
70 km/h = 19.44 m/s
Finally, we shall determine the height. This can be obtained as follow:
Initial velocity (u) = 0 m/s
Final velocity (v) = 19.44 m/s
Acceleration due to gravity (g) = 10 m/s²
Height (h) =?
v² = u² + 2gh
19.44² = 0² + (2 × 10 × h)
377.9136 = 0 + 20h
377.9136 = 20h
Divide both side by 20
h = 377.9136 / 20
h = 18.9 m
Thus, the car will fall from a height of 18.9 m
Answer:
5.72 s
Explanation:
From Newton's law, F = ma
The East is +ve direction, Hence,
F = +8930 N
m = 2290 kg
a = ?
8930 = 2290 × a
a = 8930/2290 = 3.90 m/s²
So, we will find the time it takes the car to stop using the equations of motion
a = 3.90 m/s²
u = initial velocity of the car = - 22.3 m/s (the velocity is to the west)
v = final velocity of the car = 0 m/s (since the car comes to rest)
t = time taken for the car to come to rest = ?
v = u + at
0 = - 22.3 + (3.90)(t)
3.9t = 22.3
t = 5.72 s
Answer: Acceleration
Detailed Explanation:
Acceleration is defined as the rate of change of velocity.
Answer: 6250 joules
Explanation:
The work needed to lift an object of mass M by a height H is equal to:
w = M*g*H
where h = 10m/s^2
then the total work that he did is equal to the sum of the work for every stone:
W = (100kg*g*H) + (120kg*g*H) + (140kg*g*H) + (160kg*g*H) + (180kg*g*H)
= (100kg + 120kg + 140kg + 160kg + 180kg)*g*H
= (500kg)*g*H
and now we can repalce g by 10m/s^2 and H by 125cm
But you can notice that we have two different units of distance, so knowing that 100cm = 1m
we can write H = 125cm = (125/100) m = 1.25 m
Then we have:
H = 500kg*10m/s^2*1.25m = 6250 J
