Finding speed of a falling brick using distance and the acceleration of gravity

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Homework Help Overview

The discussion revolves around calculating the speed of a falling brick after it has dropped a distance of 30 meters under the influence of gravity, which is given as 10 m/s². The original poster expresses confusion regarding the relationship between distance, time, and speed in this context.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss the use of the formula for speed as distance divided by time, questioning its applicability in this scenario where acceleration due to gravity is involved. There is a mention of the SUVAT equations and a request for clarification on their use.

Discussion Status

The conversation is ongoing, with some participants providing guidance on the importance of the SUVAT equations for solving the problem. The original poster acknowledges a lack of familiarity with these equations and expresses a desire for further explanation.

Contextual Notes

There is an indication that the original poster may be confusing speed with acceleration, and there are references to different interpretations of the problem's solution, including a friend's suggestion of an answer that differs from the calculations presented.

vytrx
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Homework Statement
A supervisor 1.8m tall visits a construction site a brick resting at the edge of a roof 50m above the ground suddenly falls at the instant when the brick has fallen 30m without encountering any air resistance, the supervisor sees the brick coming down directly towards him from above as shown in the following figure. (attached) Calculate the speed of the brick after it has falled 30 m from the roof
Relevant Equations
Speed=distance/time
acceleration of gravity is 10m/s^2
Since the brick has fallen 30m and the acceleration of gravity is 10m/s^2 the brick would have fallen 3 seconds speed of brick would then be 30/3 leaving the answer at 10m/s?I am new to physics and this question has left me stumped
 

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vytrx said:
Relevant Equations:: Speed=distance/time
That's only true for constant speed. Or, in simple cases, for calculating the average speed.

Do you know the SUVAT equations?

vytrx said:
Since the brick has fallen 30m and the acceleration of gravity is 10m/s^2 the brick would have fallen 3 seconds
You may be confusing speed and acceleration here.
vytrx said:
speed of brick would then be 30/3 leaving the answer at 10m/s?
This is not correct.

:welcome:
 
PeroK said:
That's only true for constant speed. Or, in simple cases, for calculating the average speed.

Do you know the SUVAT equations?You may be confusing speed and acceleration here.

This is not correct.

:welcome:
No I'm not familiar with the SUVAT equations, yes I may be confusing the two would you care to explain how this question is done? I've asked one of my friends that said that the answer was 24.5 but I'm not entirely sure how to get there
 
vytrx said:
No I'm not familiar with the SUVAT equations, yes I may be confusing the two would you care to explain how this question is done? I've asked one of my friends that said that the answer was 24.5 but I'm not entirely sure how to get there
The SUVAT equations are the starting point for a study of physics, so you'll need to learn about them. Try this to get you started.

https://www.ncl.ac.uk/webtemplate/a...mechanics/kinematics/equations-of-motion.html
 
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