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.
Answer:
Change in potential energy of the block-spring-Earth
system between Figure 1 and Figure 2 = 1 Nm.
Explanation:
Here, spring constant, k = 50 N/m.
given block comes down eventually 0.2 m below.
here, g = 10 m/s.
let block be at a height h above the ground in figure 1.
⇒In figure 2,
potential energy of the block-spring-Earth
system = m×g×(h - 0.2) + 1/2× k × x². where, x = change in spring length.
⇒ Change in potential energy of the block-spring-Earth
system between Figure 1 and Figure 2 = (m×g×(h - 0.2)) - (1/2× k × x²)
= (1×10×0.2) - (1/2×50×0.2×0.2) = 1 Nm.
Answer:
B:The breakdown of rocks into smaller rocks
Explanation:
Physical weathering is breaking down rocks, but it doesn't change what the rock is made out of.
It will provide a clear picture of current system functions before any modifications or improvements are made is a benefit if they use the four-model approach.
<u>Option: D</u>
<u>Explanation:</u>
The four model approach is followed by number of analyst which showcase that they construct the physical and logical model of both current and new system. The most important advantage of such approach is it portrays transparent image of ongoing system, before one apply any modification or variation. This is necessary because the flaws which generated earlier in system may affect the SDLC phases and outcome of such process may result into unsatisfied user by paying additional cost. This can be avoided by taking additional steps which make it worth it. The major disadvantage of such approach is the added time and cost of constructing model in both current system.
