<u>Answer:</u>
"The Sun's diameter is about five times that of Earth" is not true about the sun.
<u>Explanation:</u>
The Sun at the pivotal of the solar system is a star and covers 99.86% of the total mass of the system. Approximately 73% mass of the sun is due to hydrogen gas while nearly 25% mass due to helium and for the remaining mass small amount of heavier elements like carbon, oxygen, neon and iron are responsible.
The diameter of the sun is 864,000 miles or 1.39 million km or 109 times of the Earth while mass is 330,000 times of the Earth's mass. Sun is a almost perfect sphere of hot plasma with internal convective motion responsible for production of a magnetic field through a dynamo process. And the most important source of energy on Earth for life.
You need to divide the motion into its component: vertical and horizontal motion.
The time taken to fall vertically from the cliff is equal to the time taken to move horizontally.
Using the vertical component, which is an accelerated motion with an initial velocity equal to zero, we can solve for t:
h = 1/2 · g · t²
t = √(2·h / g)
= √(2·50 / 9.8)
= 3.2 s
Horizontally, it is a constant motion:
d = v · t
= 20 · 3.2
= 64 m
The ball will strike the ground at a distance of 64 meters from the cliff.
<span>What is the quality of the sound of a fire truck’s siren when it moves toward a stationary hearer?
Its High Pitched
</span>
What is the quality of the sound of a fire truck’s siren when it moves away from a stationary hearer?
Its Low Pitched
Answer:
See the explanation.
Explanation:
The speeds of sound depend upon the temperature of the medium. As the temperature increased in the afternoon, the speed of sound increases. Then the time taken by reflected sound will be less than 0.1 sec in the afternoon. And to hear an echo the time gap between an original sound and reflected sound must be at least 0.1 sec. That is why the student could not hear the echo at all in the afternoon.
Newton is the SI unit of force . Newton is the name of a British scientist and the name of unit is to honour him. The unit is actually Kg.m/s 2 The unit can be derived by the formula. Take the example of weight. It's formula is W = mg . We know that the unit of mass is kg and gravity is m/s 2 so the unit of weight becomes kg.m/s 2 This unit is known as a Newton. It is always given a capital letter because it is someone's name. Other units that are always capitalised (upper case) are Ampere (Amp), Watt, Volt, Coulomb, Kelvin, Celsius, Fahrenheit, Curie, Roentgen because they are also people's names.
