Power delivered = (energy delivered) / (time to deliver the energy)
Power delivered = (4,000 J) / (0.5 sec)
Power delivered = 8,000 watts
I'm a little surprised to learn that Electro draws his power from the mains. This is VERY good news for Spiderman ! It means that Spiderman can always avoid tangling with Electro ... all he has to do is stay farther away from Electro than the length of Electro's extension cord.
But OK. Let's assume that Electro draws it all from the mains. Then inevitably, there must be some loss in Electro's conversion process, between the outlet and his fingertips (or wherever he shoots his bolts from).
The efficiency of Electro's internal process is
<em>(power he shoots out) / (power he draws from the mains) </em>.
So, if he delivers energy toward his target at the rate of 8,000 watts, he must draw power from the mains at the rate of
<em>(8,000 watts) / (his internal efficiency) . </em>
Answer:
A_negative
B_positive
C_positive
D_positive
E_negative
Explanation:
according to the law of electrostatic which is
like charge repels and unlike charge attract.
Answer:
, attractive.
Explanation:
For calculating this force we use the Coulomb Law:

Where
is the Coulomb's constant,
and
the values of each charge and r the distance between them.
Since the Coulomb's constant as I wrote it is in S.I. we have to write all the magnitudes in that system of units, and substitute:

This force is attractive since both charges are of opposite sign.
Year9 formula: 180 (n-2)
Answer: 360
Answer:
skid distance = 180 m
Explanation:
given,
mass of the car = 1000 Kg
speed of the car = 40 Km/hr
distance to stop = 20 m
if speed is now = 120 Km/he
distance to stop = ?
from given question we can state that,
Work done by the friction is equal to the change in kinetic energy of the car.
............(1)
And we also know that work is directly proportional to displacement
W = F × x...........................(2)
from the equation (1) and (2)
x ∝ v²
now,
here velocity is increased from 40 km/h to 120 km/h means velocity is increase 3 times
so displacement will be equal to 3² or 9 times
hence, skid distance will be equal to 9 x 20 = 180 m
skid distance = 180 m