Answer:
The "trolleys" did not collide with each other because <em>their poles repelled. </em>
Explanation:
Magnets have poles located at their ends and these are the "north pole" and the "south pole."
If the north pole of one magnet will be faced to the south pole of another magnet, <em>they will attract each other</em> or <u>pull towards each other.</u> The opposite will happen when the south pole of one magnet will be faced with the same pole from another magnet. <em>They will repel each other</em> or<u> pull away from each other.</u>
Since the magnets attached to the trolleys were U-shaped, this means that the north and south poles are located at the<u> end of the magnets, which face the same direction. </u>So, once the magnets of the two trolleys move towards each other, their poles will repel because same poles will face each other.
So, this explains the answer.
Answer:
Acceleration,
Explanation:
Given that,
Initial velocity, u = 20 m/s
Final velocity, v = 60 m/s
Time, t = 10 s
We need to find the acceleration of the car. It is equal to the change in velocity divided by time.
So, the acceleration of the car is .
... The top branch of the 3-branched parallel block ... the 9 and 6 in series ...
is equivalent to a single resistor of 15 ohms.
... The 3-branched parallel block boils down to (30, 10, and 15) in parallel.
That's (1/30 + 1/10 + 1/15)⁻¹ = 5 ohms.
... The 5-ohm-equivalent block and the 20-ohm resistor form a
voltage divider across the battery.
The voltage across the 5-ohm-equivalent block is (5/25 x 30v) = 6v .
... The top branch of the block is equivalent to a (9 + 6) = 15-ohmer.
With 6v across its ends, the current through that branch is (6/15) = 0.4A .
... With 0.4A flowing through it, the 9-ohm resistor is dissipating
I²R = (0.4A)² (9 ohms) = (0.16 A²) (9 ohms) = 1.44 W (choice-3)
First we need to find the voltage difference between the initial and final location of the electron.
Since the electron travelled for a distance d=5 m in an uniform electric field of intensity E=300 N/C, the voltage difference between the final and initial location is
And then, we can calculate the change in potential energy of the electron, which is the product between the charge of the electron and the voltage difference:
And the negative sign is due to the fact that we assumed the electron traveled in the natural direction of the electric field, so traveling from a point at lower voltage to a point at higher voltage (the sign of
is positive), so since it's a negative charge the electron is losing potential energy.
What do you need to know about them?