If the period of a satellite is T=24 h = 86400 s that means it is in geostationary orbit around Earth. That means that the force of gravity Fg and the centripetal force Fcp are equal:
Fg=Fcp
m*g=m*(v²/R),
where m is mass, v is the velocity of the satelite and R is the height of the satellite and g=G*(M/r²), where G=6.67*10^-11 m³ kg⁻¹ s⁻², M is the mass of the Earth and r is the distance from the satellite.
Masses cancel out and we have:
G*(M/r²)=v²/R, R=r so:
G*(M/r)=v²
r=G*(M/v²), since v=ωr it means v²=ω²r² and we plug it in,
r=G*(M/ω²r²),
r³=G*(M/ω²), ω=2π/T, it means ω²=4π²/T² and we plug that in:
r³=G*(M/(4π²/T²)), and finally we take the third root to get r:
r=∛{(G*M*T²)/(4π²)}=4.226*10^7 m= 42 260 km which is the height of a geostationary satellite.
In a block and tackle, some friction in the pulleys will reduce the mechanical advantage of the machine. To include friction in a calculation of the mechanical advantage of a block and tackle, divide the weight of the object being lifted by the weight necessary to lift it.
Hope this helps
Answer: When you speak into the can, your voice creates air vibrations that travel into the can, vibrate the bottom of the can, which in turn vibrates the string all the way over to the other can, in turn vibrating the other can's bottom, then the air again.
Explanation:
Answer:
It is the way you see someone or something
Answer:
True statements:
Power is the rate at which work is done.
Power is the rate at which energy is transformed.
The SI unit of power is watt.
A person is limited in the total work he or she can do by the rate at which energy can be transformed.
Explanation:
The above statements are true.
1. Power is defined as the rate at which work is done.
2. Power is the rate at which energy is transformed. Whenever energy changes its form, or moves from one place to another, the rate at which it makes those changes is described as power.
3. The SI Unit of power is watts. If 1 joule of energy is converted by an object in 1 second then its power is called one watt.
So, the statement<em> 'the SI unit of power is the horsepower' is</em> false.
4. A person is limited in the total work he or she can do by the rate at which energy can be transformed i.e, his power. He is not only limited by the total energy required.
So, the statement <em>'A person is limited in the total work he or she can do only by the total energy required'</em> is not completely true.
