The answer is the first option. The one about doing your best. trust me I read the book today!
Answer: wavelength=velocity×period
Explanation:the relation between velocity, wavelength and period is
Wavelength=velocity×period
Answer:
69.74 N
Explanation:
We are given that
Weight of sled=49 N
Coefficient of kinetic friction
Weight of person=585 N
Total weight==mg=49+585=634 N
We know that
Force needed to pull the sled across the snow at constant speed,F=Kinetic friction

Where N= Normal=mg

Hence, the force is needed to pull the sled across the snow at constant speed=69.74 N
Let
be the height of the building and thus the initial height of the ball. The ball's altitude at time
is given by

where
is the acceleration due to gravity.
The ball reaches the ground when
after
. Solve for
:


so the building is about 16 m tall (keeping track of significant digits).
A step-down transformer has more loops in : A. Primary coil
Primary coil refers to the coil to which alternating voltage is supplied. It's usually connected to the AC supply
hope this helps