Average speed = total distance / total time
total distance = 40 + 20 = 60km
total time taken = 10 + 5 = 15 minutes
Average speed = 60/15 = 4km/min
See the attached picture:
Answer:
a) α=7.9x10^-4 rad
b) θ=1.12x10^-4 rad
c) The Earth and the Moon cannot be seen without a telescope.
Explanation:
In this exercise we will use the concepts of angular resolution, which depends on both the wavelength of the rays and the diameter of the eye or lens on the meter. Its unit of measure is the radian. The attached image shows the solution step by step.
Answer:
a. 2143 turns/m
b. 111.5 m
Explanation:
a. The minimum number of turns per unit length (N/L) can be found using the following equation:


Hence, the minimum number of turns per unit length is 2143 turns/m.
b. The total length of wire is the following:

Since each turn has length 2πr of wire, the total length is:

Therefore, the total length of wire required is 111.5 m.
I hope it helps you!
Answer:
The second object takes 2.28 s to fall the 25.5 m.
Explanation:
In this case, both objects take the same time to fall, since <em>no vertical velocity is added </em>to any of them.
You can also confirm this by sepparating the second's object movement into its two directions: in the horizontal one, we have <em>linear uniform motion, </em>and in the vertical one, we have <em>free fall, </em>with exactly the same characteristics as for the first object.