Answer:
a) w = 4.24 rad / s
, b) α = 8.99 rad / s²
Explanation:
a) For this exercise we use the conservation of kinetic energy,
Initial. Vertical bar
Emo = U = m g h
Final. Just before touching the floor
Emf = K = ½ I w2
As there is no friction the mechanical energy is conserved
Emo = emf
mgh = ½ m w²
The moment of inertial of a point mass is
I = m L²
m g h = ½ (m L²) w²
w = √ 2gh / L²
The initial height h when the bar is vertical is equal to the length of the bar
h = L
w = √ 2g / L
Let's calculate
w = RA (2 9.8 / 1.09)
w = 4.24 rad / s
b) Let's use Newton's equation for rotational motion
τ = I α
F L = (m L²) α
The force applied is the weight of the object, which is at a distance L from the point of gro
mg L = m L² α
α = g / L
α = 9.8 / 1.09
α = 8.99 rad / s²
<span>1.37 m/s
Assuming her initial velocity is totally horizontal and her vertical velocity is only affected by gravity, let's first calculate how much time she has until she reaches the ledge 8.00 m below her.
d = 1/2AT^2
8.00m = 1/2 * 9.8 m/s^2 * T^2
Solve for T
8.00 m = 4.9 m/s^2 * T^2
Divide both sides by 4.9 m/s^2
1.632653061 s^2 = T^2
Take square root of both sides
1.277753 s = T
So we now know that she has 1.277753 seconds in which to reach a horizontal distance of 1.75 m. So how fast does she need to be going?
1.75 m / 1.277753 s = 1.369592 m/s
Since we only have 3 significant figures in our data, round the result to 3 figures giving 1.37 m/s</span>
Answer:
Explanation:
1) Make sure the service portion of the structure stays above the highest probable water level.
2) Make sure the support structure in contact with the water can withstand the tidal flows
3) Consider whether the added restriction of the proposed structure will altar the height of, or water velocity contained in, the tidal exchanges.
4) Consider whether a dock needs to have mechanisms to compensate for large sea level changes.
Answer:
She should use a measuring tape
Explanation:
A student measures her height with a meter stick and gets a result of 1.5 m tall. This may not be as accurate as possible due to the fact that a meter stick has a maximum length of 1m which means an error could have occurred when she had to mark a point and then measure the remaining 0.5m.
She can however measure her height with greater accuracy and precision with a meter tape which has a wider measurement range and there won’t be any need to measure twice.
Answer:
Below
Explanation:
You can use this formula to find the time it will take the driver :
finalvelocity = initialvelocity + acceleration (time)
Just plug in the values and rearrange :
6.94 m/s = 0 m/s + 1.5m/s^2 (t)
6.94 m/s = 1.5m/s^2 t
4.6366 s = t
Therefore it takes the driver 4.6 seconds to accelerate to 25 km/h
Hope this helps! Best of luck <3
