Answer:
96%
Explanation:
To find the values of the motor efficiency you use the following formula:
P_o: output power = 864J/0.5min=864J/30s=28.8W
P_i: input power = I*V = (3A)(12V) = 36W
By replacing this values you obtain:
hence, the motor efficiency is about 96%
traslation:
Pentru a găsi valorile eficienței motorului, utilizați următoarea formulă:
P_o: putere de ieșire = 864J / 0.5min = 864J / 30s = 28.8W
P_i: putere de intrare = I * V = (3A) (12V) = 36W
Înlocuind aceste valori obțineți:
prin urmare, eficiența motorului este de aproximativ 96%
Answer:
The heat transferred into the system is 183.5 J.
Explanation:
The first law of thermodynamics relates the heat transfer into or out of a system to the change of internal and the work done on the system, through the following equations.
ΔU = Q - W
where;
ΔU is the change in internal energy
Q is the heat transfer into the system
W is the work done by the system
Given;
ΔU = 155 J
W = 28.5 J
Q = ?
155 = Q - 28.5
Q = 155 + 28.5
Q = 183.5 J
Therefore, the heat transferred into the system is 183.5 J.
Answer;
D. The car would begin to move in the direction it was headed in a straight line.
Explanation;
-Centripetal force is any net force causing uniform circular motion. The direction of a centripetal force is toward the center of curvature, the same as the direction of centripetal acceleration.
-The centripetal force causing the car to turn in a circular path is due to friction between the tires and the road. A minimum coefficient of friction is needed, or the car will move in a larger-radius curve and leave the roadway.
-Therefore,If the centripetal and thus frictional force between the tires and the roadbed of a car moving in a circular
path were reduced then the car would begin to move in the direction it was headed in a straight line.
Answer:
The net force acting on this object is 180.89 N.
Explanation:
Given that,
Mass = 3.00 kg
Coordinate of position of 
Coordinate of position of 
Time = 2.00 s
We need to calculate the acceleration
For x coordinates
On differentiate w.r.to t
On differentiate again w.r.to t
The acceleration in x axis at 2 sec
For y coordinates
On differentiate w.r.to t
On differentiate again w.r.to t
The acceleration in y axis at 2 sec
The acceleration is
We need to calculate the net force
The magnitude of the force
Hence, The net force acting on this object is 180.89 N.
