13 cm
just solved the same question on mastering physics<span />
Answer:
Actually, gravity is the weakest of the four fundamental forces. Ordered from strongest to weakest, the forces are 1) the strong nuclear force, 2) the electromagnetic force, 3) the weak nuclear force, and 4) gravity.
Answer:
88.8 m/s= Speed of wave propagation in the required mode.(3 loops)
Explanation:
When there are 3 loops.
the total length = L = 3 λ /2
⇒ λ = 2 L / 3 = 2 ( 1.11 ) / 3 = 0.74 m
Velocity = v = f λ = (120)(0.74) = 88.8 m/s
Answer:
The sled needed a distance of 92.22 m and a time of 1.40 s to stop.
Explanation:
The relationship between velocities and time is described by this equation: 
, where 
is the final velocity, 
is the initial velocity, 
the acceleration, and 
is the time during such acceleration is applied.
Solving the equation for the time, and applying to the case: 
, where 
because the sled is totally stopped, 
is the velocity of the sled before braking and, 
is negative because the deceleration applied by the brakes.
In the other hand, the equation that describes the distance in term of velocities and acceleration:
, where 
is the distance traveled, is the initial velocity, the time of the process and, is the acceleration of the process.
Then for this case the relationship becomes: 
.
<u>Note that the acceleration is negative because is a braking process.</u>
