Answer:
fo = 378.52Hz
Explanation:
Using Doppler effect formula:

where
f' = 392 Hz
C = 340m/s
Vb = 20m/s
Va = 31m/s
Replacing these values and solving for fo:
fo = 378.52Hz
Answer:
The hypothesis may or may not be true and needs to be tested. It might be the answer to the problem. Hence, it must be tested thoroughly. When these predictions are tested again and again in independent scientific experiments and gets verified, the hypothesis is converted into a scientific theory.
I disagree with that opinion, and I have solid Physics to back me up.
The forces of gravity are always equal in both directions. The sun pulls the Earth with exactly the same force with which the Earth pulls the sun.
It may seem weird, but your weight on Earth is exactly the same as the Earth's weight on you. For the same reason.
Answer:
If you're talking about the sun than:
Time, Distance and Shielding Time, distance, and shielding actions minimize your exposure to radiation in much the same way as they would to protect you against overexposure to the sun:
If you're talking about the ocean than:
Water safety precautions for teens and young adults:
Never go into the water if you can’t swim.
If you can’t swim, learn. Any age can receive swimming lessons.
Always wear a life jacket while boating or taking part in boating activities such as tubing or skiing.
Never swim alone or in an unsupervised area.
Know your swimming strength.
Don’t rough house around water. Never push, jump on or hang on to others in or around water.
Never drink alcohol while taking part in water or boating activities. Alcohol affects your motor skills therefore making it harder to swim, float, keep balance or drive.
Explanation:
Weight is equivalent to the product of the mass of an object and the strength of the gravitational field.
Using:
F = ma
a = 8.2 / 5
a = 1.64 N/kg
The gravitational field strength is equivalent to 1.64 N/kg.