Answer:
0.833
Explanation:
Power = energy / time
Power = force × distance / time
Power = force × velocity
P = (850 kg) (9.8 m/s²) (1.00 m/s)
P = 8330 W
P = 8.33 kW
The efficiency of the motor is therefore:
e = 8.33 kW / 10.0 kW
e = 0.833
Answer:
Explanation:
There are countless household appliances in every single house. One appliance with a low power rating would be a ceiling fan. On average ceiling fans consume roughly 60w and are found in the majority of houses. On the other side of the spectrum, we have a high power-rating appliance such as a microwave. Microwaves use anywhere between 1000w to 1800w of power in order to function correctly. This is very large power consumption and one of the highest power ratings found for appliances in a household.
Answer:
acceleration 8 km/h/s south
Explanation:
First of all, let's remind that a vector quantity is a quantity which has both a magnitude and a direction.
Based on this definition, we can already rule out the following two choices:
distance: 40 km
speed: 40 km/h
Since they only have magnitude, they are not vectors.
Then, the following option:
velocity: 5 km/h north
is wrong, because the car is moving south, not north.
So, the correct choice is
acceleration 8 km/h/s south
In fact, the acceleration can be calculated as

where
v = 40 km/h is the final velocity
u = 0 is the initial velocity
t = 5 s is the time
Substituting,

And since the sign is positive, the direction is the same as the velocity (south).
If one of two interacting charges is doubled, the force between the charges will double.
Explanation:
The force between two charges is given by Coulomb's law

K=constant= 9 x 10⁹ N m²/C²
q1= charge on first particle
q2= charge on second particle
r= distance between the two charges
Now if the first charge is doubled,
we get 
F'= 2 F
Thus the force gets doubled.
Answer:
(c) 97 dB sound intensity level
Explanation:
We have given the intensity of the loud car horn 
We know that 
Now the sound intensity level is given by
, which is nearly equal to 97
So the sound intensity level will be 97 dB
So option (c) will be the correct option