Answer:
(i) Length of stadium, L₀ = 72 yards; width of stadium W = 55 yards (ii) 5 hours (iii) The people on earth. This is because they are not moving at relativistic speed relative to the game. (iv) The people on earth. This is because they are not moving at relativistic speed relative to the game.
Explanation:
(i) Given Length of stadium, L₀ = 120 yards, width of stadium, W₀ = 55 yards, speed of alien spaceship in direction of play, v = 0.8c
We use the equation for length contraction to determine the length of stadium L measured by the alien spaceship, since it is moving in the direction of game play and length contraction only occurs in the direction of motion. So, L = 
L₀ where β = 
v= speed of alien spaceship and c= speed of light. So, β = = 
= 0.8. Therefore, L = 
L₀= 
L₀= 
L₀ = 0.6L₀ = 0.6 × 120 = 72 yards. So, the alien spaceship measures a length of 72 yards. The alien spaceship measures a width,W of 55 yards because there is no length contraction in the direction perpendicular to that of its motion. So, W = W₀ = 55 yards.
(ii) Since the game begins at 1:30 PM Pacific Standard Time (PST) and ends 4:30 PM Pacific Standard Time (PST), the proper time t₀, which is the duration of the event is 4:30 - 1:30 = 3 hours. The time measured by the alien spaceship t (since the time dilates)is given by t = t₀/
. From (i) above β = 0.8 and t₀ = 3 hours. So, t = 3/
= 3/0.6 = 5 hours.
(iii) The people in Spanos football stadium. This is because they are not moving at relativistic speed relative to the game. Since ≈ 0 then β ≈ 0 So, L = L₀= So, L = 
L₀thus L = L₀ for the spectators in spanos football field (iv) The people in Spanos football stadium. This is because they are not moving at relativistic speed relative to the game. Since ≈ 0 then β ≈ 0. So, t = t₀/ = t₀/ = t₀.Thus t = t₀ for the spectators in spanos football field.
7. PE=0.5×700n/m×0.9m^2
0.9^2=0.81m
0.5×700×0.81= 283.5J
8. 2000=0.5×(x)×1.5m^2
1.5^2= 0.25
0.25×0.5=0.125
2000=0.125 (x)
2000/0.125=x
x=16000 n/m
9. 4000=0.5 (375 n/m)×(x)^2
0.5×187.5 (x)
4000/187.5=21.3333333333
Answer:
speed v = 0.148 m / s
velocity v = 0
Explanation:
In this exercise we must be careful that the speed is a scalar and the speed is a vector, let's start by looking for the speed
v = Δx /Δt
the distance traveled is x = 2d and the time taken is
t = 7h 30 min
let's reduce to seconds
t = 7 h 3600s / 1h + 30 min 60s / 1min = 27000 s
so the speed is
v = 2d / 27000
to finish the calculation suppose a distance traveled d = 2000 m
v = 2 2000/27000
v = 0.148 m / s
this is the raides which is the speed module
Velocity is a vector,
v = Dx / Dt
in this case the displacement is
Dx = d -d
Dx = 0
the total displacement is zero since it returns to the starting point, consequently the velocity is zero
v = 0
bold is a vector
0.200cm= 0.002km
0.002*60=0.12km/min
0.12*60=7.2km/h
7.2*24=172.8km/day
172.8*365=63072km/year
The thermal energy of an object is the energy contained in the motion and vibration of its molecules. Thermal energy is measured through temperature. The energy contained in the small motions of the object's molecules can be broken up into a combination of microscopic kinetic energy and potential energy.
