Answer:
Explanation:
If the passage of the waves is one crest every 2.5 seconds, then that is the frequency of the wave, f.
The distance between the 2 crests (or troughs) is the wavelength, λ.
We want the velocity of this wave. The equation that relates these 3 things is
and filling in:
so
v = 2.5(2.0) and
v = 5.0 m/s
Answer: c
Explanation:
Analytical methods
Answer:
310.5 J
Explanation:
The total work done by Martha is equal to the increase in gravitational potential energy of the package, which is equal to

where
(mg) = 45 N is the weight of the package
is the increase in height of the package
The package is carried up 3 flights of stairs, each one with a height of 2.3 m, so the total increase in heigth is

And so, the work done by Martha is

Answer:
57 N
Explanation:
Force on a current carrying conductor in a magnetic field
B = 12 X 10⁻⁴ T
= Bil where B is magnetic field , i is current and l is length of conductor
force required = 12 x10⁻⁴ x 47500 x 1
= 57 N