Answer:
Force, F = 187.42 N
Explanation:
It is given that,
Mass of boy, m = 30 kg
Acceleration due to gravity, 
Radius of curvature of the roller coaster, r = 15 m
Speed of the car, v = 7.3 m/s
The force acting on the boy are force of gravity and the centripetal force. The net force acting on him is as follows :



F = 187.42 N
So, he press against the seat with a force is 187.42 N. Hence, this is the required solution.
Answer:Whenever a moving object experiences friction, some of its kinetic energy is transformed into thermal energy. Mechanical energy is always transformed into thermal energy due to friction. Mechanical energy is always transformed into thermal energy due to friction.
Explanation:
Whenever a moving object experiences friction, some of its kinetic energy is transformed into thermal energy. Mechanical energy is always transformed into thermal energy due to friction. Mechanical energy is always transformed into thermal energy due to friction.
We can conclude that it is a longitudinal wave because the wave is traveling through a medium displacing particles<span>
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Hello there!
For this:
1). Convert 10km to meters!
2). Convert the 30 minutes into seconds!
3). Use the following formula to solve for speed!
speed= distance/time
Note: The units should automatically work out to m/s. :)
My goal is to make sure you understand the problem, which is why I won't be giving you the answer. It'll be more work now, but less work in the future! :)
Hope this helped!
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DISCLAIMER: I am not a professional tutor or have any professional background in your subject. Please do not copy my work down, as that will only make things harder for you in the long run. Take the time to really understand this, and it'll make future problems easier. I am human, and may make mistakes, despite my best efforts. Again, I possess no professional background in your subject, so anything you do with my help will be your responsibility. Thank you for reading this, and have a wonderful day/night!
If i was feeling harsh today, I'd say the answer to your question is impossible to obtain due to the fact that photons do not emit radiation, photons ARE the radiation emitted. Though for the sake of it, here is the method...
<u>The simple method:
</u>
E=hf
therefore f=e/h
f=(3.611x10^-15) / 6.63x10^-34)
Answer: 5.45x10^18