1) 5.79 s
2) 98.4 ft/s
Explanation:
1)
The motion of the car is a uniformly accelerated motion (it means it travels with constant acceleration), so we can find the time it takes for the car to stop by using the following suvat equation:
where
s is the distance travelled
v is the final velocity
t is the time
a is the acceleration of the car
In this problem we have:
s = 285 ft is the distance travelled
is the acceleration of the car (negative since the car is slowing down)
v = 0 ft/s is the final velocity of the car, since it comes to a stop
Solving for t, we find:
2)
The initial speed of the car can be found by using another suvat equation, namely:
where
v is the final speed
u is the initial speed
a is the acceleration
t is the time
In this problem, we have:
v = 0 is the final speed of the car
is the acceleration of the car (negative since the car is slowing down)
t = 5.79 s is the total time of motion (found in part 1)
Therefore, the initial speed of the car is:
The answer would be, the iris. Hope this helps:)
Answer:
a) dB / dA = 2
,
b) Network B Network A
2 1
4 2
6 3
Explanation:
a) The expression for grating diffraction is
d sin θ = m λ
where d the distance between two slits, λ the wavelength and m an integer that represents the diffraction range
In this exercise we are told that the two spectra are in the same position, let's write the expression for each network
Network A
m = 1
sin θ = 1 λ / dA
Network B
m = 2
sin θ = 2 λ / dB
they ask us for the relationship between the distances, we match the equations
λ / dA) = 2 λ / dB
dB / dA = 2
b) let's write the equation of the networks
sin θ = m_A λ / dA
sin θ = m_B λ / dB
we equalize
m_A λ/ dA = m_B λ / dB
we use that
dB / dA = 2
m_A 2 = m_B
therefore the overlapping orders are
Network B Network A
2 1
4 2
6 3
A constant velocity implies the two forces must be equal and opposite.
Friction acts horizontal to the ground, therefore we must find the force applied to the sled rope that acts horizontal to the ground.
Do this by resolving:
Force = 80cos53
The force opposing this is equal, and so also = 80cos53 = 48 N (2 sig. fig.)
