Answer:
66.4 m
Explanation:
To solve the problem, we can use the length contraction formula, which states that the length observed in the reference frame moving with the object (the rocket) is given by

where
is the proper length (the length measured from an observer at rest)
v is the speed of the object (the rocket)
c is the speed of light
Here we know
v = 0.85c
L = 35.0 m
So we can re-arrange the equation to find the length of the rocket at rest:

Daniddmelo says it right there, don't know why he got reported.
The potential energy (PE) is mass x height x gravity. So it would be 25 kg x 4 m x 9.8 = 980 joules. The child starts out with 980 joules of potential energy. The kinetic energy (KE) is (1/2) x mass x velocity squared. KE = (1/2) x 25 kg x 5 m/s2 = 312.5 joules. So he ends with 312.5 joules of kinetic energy. The Energy lost to friction = PE - KE. 980- 312.5 = 667.5 joules of energy lost to friction.
Please don't just copy and paste, and thank you Dan cause you practically did it I just... elaborated more? I dunno.
Answer:
The wavelength of the light is
.
Explanation:
Given that,
Distance between the slit centers d= 1.2 mm
Distance between constructive fringes 
Distance between fringe and screen D= 5 m
We need to calculate the wavelength
Using formula of width

Put the value into the formula




Hence, The wavelength of the light is
.
"The" (and any subsequent words) was ignored because we limit queries to 32 words.