Answer:
Closed system, because the speed of the car is as expected in the case where an object has uniform acceleration for a time t
Explanation:
Here in the question it is mentioned that a toy car has an initial acceleration of 2m/s² across a horizontal surface so we can say that it is acted upon by an external force
Assuming that the acceleration is constant and the reason for this assumption is there at the last
The major difference between an open system and closed system is in case of open system there will be transfer of matter and in case of closed system there will be no change in matter of the system
If acceleration is constant in case of closed system we can expect the speed of the car after a time t by using the formula
s = u×t + 0·5×a×t²
where s is the distance travelled
t is the time taken to travel that distance
u is the initial velocity
a is the acceleration of that system
But in case of open system as there will be a change of mass there will be a change in velocity of the system so in this case we cannot expect the speed of the car after a time t
And if the acceleration is not constant then we cannot say that the toy car is an open system or closed system, that is why we are assuming that the acceleration of the toy car is constant
Answer:
5 miles per hour
Explanation:
if you divide 15 by 3 you get 5, therefore the student is going 5 miles per hour.
<h2>
Answer:
</h2>
The velocity of a satellite describing a circular orbit is <u>constant</u> and defined by the following expression:
(1)
Where:
is the gravity constant
the mass of the massive body around which the satellite is orbiting
the radius of the orbit (measured from the center of the planet to the satellite).
Note this orbital speed, as well as orbital period, does not depend on the mass of the satellite. I<u>t depends on the mass of the massive body.</u>
In addition, this orbital speed is constant because at all times <u>both the kinetic energy and the potential remain constant</u> in a circular (closed) orbit.
<span>
The taut guitar string haspotencial energy which we can see in action.</span> <span>· so option a is correct.</span>
Answer:

Explanation:
From the question we are told that:
Crane Length 
Crane Mass 
Arm extension at lifting end 
Arm extension at counter weight end 
Load 
Generally the equation for Torque Balance is mathematically given by


