a brick falls off scaffold at height of 80 m above the ground it velocity AfTeR FalLInG for 2 s Is 19;6 what iS IT MAgnitudE WheN IT HITS The GRound?
V^2 = Vo^2 + 2g*h.
Vo = 0, g = 9.8 m/s^2, h = 80 m.
V = ?.
Well, it seems our brick had a pretty adventurous fall! Now, to figure out the magnitude of its velocity when it hits the ground, we can use a bit of physics and humor.
Considering the brick has fallen for 2 seconds, we can use the equation for free-fall motion: v = u + gt, where v represents the final velocity, u is the initial velocity (which is 0 in this case since the brick starts from rest), g is the acceleration due to gravity (approximately 9.8 m/s²), and t is the time.
Plugging in the given values, we have v = 0 + 9.8 * 2. So, after performing the calculation, the brick's velocity just before hitting the ground is 19.6 m/s.
So, to answer your question with a touch of humor: When the brick hits the ground, its magnitude of velocity is a whopping 19.6 m/s! Quite the speedy descent for a humble brick, wouldn't you say?
To find the magnitude of the brick's velocity when it hits the ground, we can use the following kinematic equation:
v = u + a*t
Where:
v is the final velocity (which we need to find)
u is the initial velocity (which is 0, as the brick starts falling from rest)
a is the acceleration due to gravity (-9.8 m/s^2, assuming no air resistance)
t is the time taken for the brick to fall (which is 2 seconds, as given)
Plugging in these values into the equation, we have:
v = 0 + (-9.8 m/s^2) * 2 s
v = -19.6 m/s
The negative sign indicates that the velocity is in the downward direction. However, since we are looking for the magnitude, we disregard the negative sign:
Magnitude of velocity = |-19.6 m/s| = 19.6 m/s
Therefore, the magnitude of the brick's velocity when it hits the ground is 19.6 m/s.
To find the magnitude of the velocity when the brick hits the ground, you can use the equation of motion:
v = u + at
Where:
- v is the final velocity (the velocity right before the brick hits the ground)
- u is the initial velocity (the velocity at the beginning of the fall, which is 0 m/s in this case as the brick starts from rest)
- a is the acceleration due to gravity (-9.8 m/s², assuming downward direction)
- t is the time taken for the fall (2 s in this case)
Given that the brick falls from a height of 80 m, we can calculate the time taken to fall using the equation:
s = ut + (1/2)at²
Where:
- s is the distance (the height of the scaffold, which is 80 m)
- u is the initial velocity (0 m/s)
- a is the acceleration due to gravity (-9.8 m/s²)
- t is the time taken for the fall
Rearranging this equation to solve for t:
80 = (1/2)(-9.8)t²
Simplifying:
-4.9t² = -80
Divide both sides by -4.9:
t² = 16.3265
Taking the square root of both sides:
t ≈ 4.04 s
Now, we can use the time (t = 2 s) in the first equation to calculate the final velocity (v):
v = u + at
v = 0 + (-9.8)(2)
v = -19.6 m/s
The negative sign indicates that the velocity is downward. However, since the question asks for the magnitude, we discard the negative sign and take the absolute value:
Magnitude of the velocity when the brick hits the ground = |v| = |-19.6| = 19.6 m/s
Therefore, the magnitude of the velocity when the brick hits the ground is 19.6 m/s.