Falling brick speed - equation needed

In summary, the equation for calculating the speed of a falling brick is v = gt, where v is the velocity or speed of the brick, g is the acceleration due to gravity (9.8 m/s^2), and t is the time in seconds. To use this equation, you need to know the acceleration due to gravity and the time it takes for the brick to fall. The mass of the brick does not affect its falling speed according to this equation. This equation can also be used to calculate the speed of a falling brick on any planet, as long as the acceleration due to gravity is known. Other factors such as air resistance, wind, and the shape/size of the brick may affect the speed, but the equation assumes
  • #1
[Cat]
1
0
I have a question in my work book that I cannot solve as I can't find the correct equation. The question is:

What speed will the brick have after falling through a distance of 20 metres? U= at rest. There are no other constants given. What equation would I use to solve this problem?

(I have looked in the back of the book and the answer is:19.8 m/s)

Thanks,
Cat.
 
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  • #2
Think conservation of energy. Compare the initial and final energies at each state and equate them.
 
  • #3
v**2=u**2+2as
 
Last edited:

1. What is the equation for calculating the speed of a falling brick?

The equation for calculating the speed of a falling brick is v = gt, where v is the velocity or speed of the brick, g is the acceleration due to gravity (9.8 m/s^2), and t is the time in seconds.

2. How do you use the equation to calculate the speed of a falling brick?

To use the equation, you need to know the acceleration due to gravity, which is a constant (9.8 m/s^2), and the time it takes for the brick to fall. Plug in these values into the equation v = gt and solve for v, which will give you the speed of the falling brick in meters per second.

3. Does the mass of the brick affect its falling speed?

According to the equation v = gt, the mass of the brick does not affect its falling speed. This is because the acceleration due to gravity is a constant and does not change based on an object's mass.

4. Can you use this equation to calculate the speed of a falling brick on any planet?

Yes, as long as you know the acceleration due to gravity on that planet, you can use the equation v = gt to calculate the speed of a falling brick. Keep in mind that the acceleration due to gravity may be different on different planets.

5. Are there any other factors that could affect the speed of a falling brick?

Yes, there are other factors that could affect the speed of a falling brick, such as air resistance, wind, and the shape/size of the brick. These factors may alter the acceleration or time it takes for the brick to fall, resulting in a different speed. However, the equation v = gt assumes that there is no air resistance and the brick is falling in a vacuum.

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