I think you're saying that once you start pushing on the cars, you want to be able to stop each one in the same time.
This is sneaky. At first, I thought it must be both 'c' and 'd'. But it's not
kinetic energy, for reasons I'm not ambitious enough to go into.
(And besides, there's no great honor awarded around here for explaining
why any given choice is NOT the answer.)
The answer is momentum.
Momentum is (mass x speed). Change in momentum is (force x time).
No matter the weight (mass) or speed of the car, the one with the greater
momentum is always the one that will require the greater (force x time)
to stop it. If the time is the same for any car, then more momentum
will always require more force.
The answer is B.
A cannot be the answer is melting is a physical change. No chemical reaction took place.
B is the answer as it is a EXOTHERMIC REACTION so heat will be given off.
C cannot be the answer as dissolving is basically atoms becoming ions, not a chemical reaction whereby a reactant reacts with another reactant to form a product.
D cannot be the answer. Same reason as for why A is not the answer.
Cheers.
The frequency of the wheel is given by:

where N is the number of revolutions and t is the time taken. By using N=100 and t=10 s, we find the frequency of the wheel:

And now we can find the angular speed of the wheel, which is related to the frequency by:
Answer:
The speed of the 270g cart after the collision is 0.68m/s
Explanation:
Mass of air track cart (m1) = 320g
Initial velocity (u1) = 1.25m/s
Mass of stationary cart (m2) = 270g
Velocity after collision (V) = m1u1/(m1+m2) = 320×1.25/(320+270) = 400/590 = 0.68m/s
For Ethernet, if an adapter determines that a frame it has just received is addressed to a different adapter
a. it discards the frame without sending an error message to the network layer
b. it sends a NACK (not acknowledged frame) to the sending host
c. it delivers the frame to the network layer, and lets the network layer decide what to do
d. it discards the frame and sends an error message to the network layer
Answer:
Option A
Explanation:
The nodal address has to match the signal message address for it to function well but if the it doesn't match the nodal receiver address, it disregards it.