Physics 1050 Laboratory #3 Force and Acceleration _____________________________________________________________________

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Force and Acceleration

Newton’s second law is usually written 𝛴𝐹 = 𝑚𝑎 and states The net force on an object is equal to the product of its mass and acceleration. For an object to accelerate, there must be a net force. This is a vector expression and is equivalent to the following component equations

𝛴𝐹& = 𝑚𝑎& 𝛴𝐹( = 𝑚𝑎(. Objects on an inclined plane will accelerate down the plane provided the component of the gravitational force directed parallel to the plane exceeds the frictional force. The average acceleration over a time interval from 𝑡+ to 𝑡, is given as

𝑎 =𝛥𝑣𝛥𝑡 =

𝑣, − 𝑣+𝑡, − 𝑡+

where 𝑣+ and 𝑣, are the velocity at times 𝑡+ and 𝑡, respectively. Acceleration is also given by the slope of a velocity vs. time graph. In this experiment the position as a function of time of a moving cart will be measured using a motion sensor. The velocity as a function of time will be calculated with the LoggerPro software.

Physics 1050 Laboratory #3 Force and Acceleration _____________________________________________________________________

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Prelab Questions These questions need to be completed before entering the lab. Show all workings. Prelab 1 Draw the free body diagram for the cart on an inclined plane. Break the weight vector into components. Prelab 2 Does the acceleration of the cart depend on mass? Explain.

Markers Initials

Staple completed prelab to this page

Physics 1050 Laboratory #3 Force and Acceleration _____________________________________________________________________

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Name and Student Number: ___________________________________ Date: ___________________________________ Partner: ___________________________________ Part I : Introduction Part II: Apparatus & Set up Part III: Experiment Table 1: Cart sliding down inclined plane.

Run q (degrees) sin q a (m/s2)

1

2

3

4

5

6 Return to the lab manual: QUESTION 1:

x

y

€

θ

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QUESTION 2:

QUESTION 3:

Return to the lab manual: Part IV: Analysis TABLE 2: Slope and intercept of acceleration versus sin q graph.

Value Uncertainty Units

Slope

Intercept

QUESTION 4:

Staple graph to the opposing page

Physics 1050 Laboratory #3 Force and Acceleration _____________________________________________________________________

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QUESTION 5:

QUESTION 6:

Part V: Summary

QUESTION 7:

QUESTION 8: