Answer:
(a)2.7 m/s
(b) 5.52 m/s
Explanation:
The total of the system would be conserved as no external force is acting on it.
Initial momentum = final momentum
⇒(4.30 g × 943 m/s) + (730 g × 0) = (4.30 g × 484 m/s) + (730 g × v)
⇒ 730 ×v = (4054.9 - 2081.2) =1973.7
⇒v=2.7 m/s
Thus, the resulting speed of the block is 2.7 m/s.
(b) since, the momentum is conserved, the speed of the bullet-block center of mass would be constant.

Thus, the speed of the bullet-block center of mass is 5.52 m/s.
A. The cliff was 30.7 m high
B. I also got 9.5 as the horizontal distance
Here is my work, I find making charts like this one to find knowns and unknowns can be helpful
Answer:
Rubber is an insulator.
Explanation:
Rubber is an insulator. Electricity will always travel "the path of least resistance." Rubber has a very high resistance, so electricity will go somewhere else to find ground.
12 V is the f.e.m.

of the battery. The potential difference that is applied to the motor is actually the fem minus the voltage drop on the internal resistance r:

this is equal to the voltage drop on the resistance of the motor R:

so we can write:

and using

and

we can find the current I: