Answer:
F = 5702.56 N
Explanation:
Given that,
Mass of a small car, m = 800 kg
Initial speed of the car, u = 27.8 m/s
Final speed, v = 0
Time, t = 3.9 s
We need to find the force did it take for the car to stop.
The force acting on an object is given by :

So, the magnitude of force acting on the car to stop is 5702.56 N.
The gravitational potential energy of the weight changes to motion energy when the weight moves down and the paddle wheel spins. The motion energy changes to thermal energy, causing the water’s temperature to rise.
(fast explanation for my fellow edmentum kids :))
Explanation:
We know,
1KN = 1000N
Then, Force(F) = 5*1000N
=5000N
Here,
Power (P)=Work(W)/Time(T)
=Force * distance/ Time (W = F*s)
= 5000*15/75
=1000
So, The power of body or object is 1000Watt.
I hope this will be helpful for you.
Answer: option d. gives the percentage of water molecules in the air.
Explanation:
#14 isn't really a Physics problem. It's more of just reading a graph.
A). When speed changes, acceleration is
(change in speed) / (time for the change) .
To be correct about it, acceleration can be positive ... when speed
is increasing ... or it can be negative ... when speed is decreasing.
So, on this graph, there are two periods of acceleration:
From zero to 2 seconds, acceleration = (8 m/s) / (4 sec) = 2 m/s² .
From 10 to 12 seconds, acceleration = (-4 m/s) / (2 sec) = -2 m/s² .
B). From 12 to16 seconds, you can read the speed right from
the graph. It's 4 m/s .
C). From 2 to 10 seconds, the objects speed is a steady 8 m/s.
Covering 8 m/s every second for 8 seconds, it covers 64 meters.
Do you remember that distance is the area under the speed/time
graph? You can see that plainly on this graph. From 2 to 10 sec,
there are 16 blocks. Each block is (2 m/s) high and (2 sec) wide,
so its area is (2 m/s) x (2 sec) = 4 meters. The area of 16 blocks
is (16) x (4 meters) = 64 meters.
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#15.
a). constant velocity on a distance graph is a line that slopes up;
constant velocity on a velocity graph is a horizontal line;
b). positive constant acceleration on a distance graph is a
line that curves up;
positive constant acceleration on a velocity graph is a
straight line that slopes up;
c). "uniformly slowing down to a stop" on a distance graph
is a line that's less and less curved as time goes on, and
eventually reaches the x-axis.
"uniformly slowing down to a stop" on a velocity graph is
a straight line that slopes down, and stops when it reaches
the x-axis.