Answer:
Explanation:
1. False
The force you apply on crate is equal and opposite to the force that crate applies on you by Newton's third law of motion.
The force must over come the static frictional force between the crate and the floor.
2. True
The object can move along another direction than the direction of net force. For example, when a car slows down, the net force is opposite to the direction of motion.
3. True
An object moving at constant velocity has zero net force acting on it.
4. False
An object at rest has forces acting on it but the summation of all the forces is zero i.e. the net force is zero.
For electrical devices . . .
Power dissipated = (voltage) x (current) =
(12 V) x (3.0 A) = 36 watts .
1 watt means 1 joule per second
(36 joule/sec) x (60 sec/min) x (10 min) = 21,600 joules
Answer:
1200 meters
Explanation:
there are 60 seconds in a minute times 2 is 120 ten times 120 is 1200
Answer:
(A) Q = 321.1C (B) I = 42.8A
Explanation:
(a)Given I = 55A−(0.65A/s2)t²
I = dQ/dt
dQ = I×dt
To get an expression for Q we integrate with respect to t.
So Q = ∫I×dt =∫[55−(0.65)t²]dt
Q = [55t – 0.65/3×t³]
Q between t=0 and t= 7.5s
Q = [55×(7.5 – 0) – 0.65/3(7.5³– 0³)]
Q = 321.1C
(b) For a constant current I in the same time interval
I = Q/t = 321.1/7.5 = 42.8A.
