Grade 12 Physics help, Kinematics

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SUMMARY

The discussion revolves around a Grade 12 Physics problem involving kinematics, specifically the motion of a child sliding down a smooth metal fire pole. The child, with a mass of 35.7 kg, descends a height of 3.10 m in 2.00 seconds. To determine the downward acceleration, the appropriate kinematic equation is used, yielding an acceleration of 0.775 m/s². The upward force of friction is not applicable in this scenario as the pole is smooth, indicating no frictional force acting on the child.

PREREQUISITES
  • Understanding of kinematic equations
  • Basic knowledge of acceleration and forces
  • Familiarity with mass and weight concepts
  • Ability to interpret motion graphs
NEXT STEPS
  • Study the kinematic equation: \( s = ut + \frac{1}{2}at^2 \)
  • Learn about the relationship between mass, weight, and gravitational force
  • Explore the concept of friction in physics, specifically in smooth surfaces
  • Practice solving problems involving constant acceleration
USEFUL FOR

Students in Grade 12 Physics, particularly those struggling with kinematics and motion concepts, as well as anyone seeking to improve their understanding of basic physics principles.

Telmob
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Homework Statement


Alright, just started physics and I've already fallen behind :(

trying to do my homeowkr and I am completely lost, no idea at all.

So here's a question which i had no idea how to do.

* A tree house has a vertical "fire pole" of smooth metal, designed for quick exits. A child of mass 35.7Kg slides down the pole with constant acceleration, starting from rest. The pole is 3.10m high. The journey to the ground takes 2.00s.
a) what is the magnitude of the downward acceleration of the child?
b) What is the magnitude of the upward force of friction exerted by the pole of the child?

Also, i looked in the back of my textbook and in my notes, and i still don't know what magnitude means. Or how to get it for that matter.



Homework Equations


I know for this problem to find a) i could use the equation a= external friction/mass
but how do i find a? is it just g= -9.8m/s² or does it have to do with the kids weight?
and i have no idea how to get the external friction or what exactly it is.

I know this right now
m=35.7Kg
T= 2s
Height= 3.1m high
g= -9.8m/s²


i don't know if this is enough information but please help me, its been 2 weeks and I am already behind, I've gone to extra help after school, but its the same teacher and i guess i just don't understand him.
 
Physics news on Phys.org
For the first part don't use forces... just use kinematics. You can immediately calculate acceleration by using the right equation.
 

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