Answer:
13 m/s
Explanation:
I assume we are ignoring friction.
The boy's PE will all be converted to KE at the bottom of the hill.
to find PE = mgh we need to know h
h = 50 sin 10 = 8.68 meters
then: PE = 20 * 9.81 * 8.68 =<u> 1703.49</u> j
KE = 1/2 m v^2 = <u>1703 .49</u>
v = 13 m/s
Answer:
The average velocity is 180 km/hr
Explanation:
Given;
initial velocity, u = 60 km per hour
final velocity, v = 120 km per hour
initial time = 1 hour
final time = 2 hour
Initial position = 60 km/h x 1 hour = 60 km
final position = 120 km/h x 2 hour = 240 km
The average velocity is given by;

Therefore, the average velocity is 180 km/hr
Answer:
The time is 133.5 sec.
Explanation:
Given that,
One side of cube = 10 cm
Intensity of electric field = 11 kV/m
Suppose How long will it take to raise the water temperature by 41°C Assume that the water has no heat loss during this time.
We need to calculate the rate of energy transfer from the beam to the cube
Using formula of rate of energy


Put the value into the formula


We need to calculate the amount of heat
Using formula of heat


Put the value into the formula


We need to calculate the time
Using formula of time

Put the value into the formula


Hence, The time is 133.5 sec.
Answer: about 100 km[kilometers] thick
Explanation:
Answer:


Explanation:
Given Data:
Numbers of times Telescope cycled around the earth in 6 years=37,000 times
Total Distance traveled in 6 years by the Hubble Space Telescope=1,280,000,000 Km
Find:
Kilometers in one Orbit=?
Solution:
Kilometers in 37,000 Orbits=1,280,000,000 Km
Kilometers in 1 Orbit=1,280,000,000/37,000
In Scientific Notation:


Kilometers in 1 Orbit=34594.594 Km
Kilometers in 1 Orbit in Scientific notation:
