Answer:
his speeds while going to city is 10 mph and while his round trip the speed will be 9 mph
Explanation:
Let say the speed of the bicycle while he moves towards the city is "v"
now the speed of the round trip must be smaller by 1 mph
so its speed for round trip will be

now we know that total time of the motion is 19 hr
so we will have


so we will have




by solving above equation we have

so his speeds while going to city is 10 mph and while his round trip the speed will be 9 mph
Kinetic energy = (1/2) (mass) (speed²).
A Physicist in the canoe, or on a raft floating downriver next to the canoe, will say that the canoe's kinetic energy is zero.
A Physicist on the riverbank, watching the canoe drift by at 1 m/s, will say that its kinetic energy is 9 Joules.
They're both correct.
The slope of a speed-time graph is the acceleration represented by the graph.
All other parts of this question refer to a lab experiment or exercise
where I was not present, but Zeesam16 was. Therefore I have no data
with which to answer the rest of the question, and hope that Zeesam can
handle it.
The solution you should use is Hooke's law: F=-kx
It should have the same signs because they repel due to the stretch of the spring.
a. Since there is a constant energy within the spring, then Hooke's law will determine the possible algebraic signs. The solution should be
<span>F = kx
270 N/m x 0.38 m = 102.6 N
</span>
b. Then use Coulomb's law; F=kq1q2/r^2 to find the charges produced in the force.