Posterous theme by Cory Watilo

1.26 Answers

1.26 Question

31 October 2011

17:36

·         1.26 understand that the upward forces on a light beam, supported at its ends, vary with the position of a heavy object placed on the beam 

 

Question 

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·         The Newtonmeters in the diagram labelled L and R are spaced 1m apart 

·         The hanging mass has a weight of 7N and is placed 0.3m from the Newtonmeter labelled R 

·         What are the readings on Newtonmeters L and R? 

 

Hints to help

·         Calculate moments about either of the Newtonmeters; moments should be balanced because the beam is stationary

·         Now calculate moments about the other Newtonmeter

·         You should now have found the readings on each Newtonmeter; is there a way to check that these answers are correct?


 

 

Fa x da = Fc x dc

7 x 0.3 = Fc x 1.0

2.1N= Fc

Fa x da = Fc x dc

7 x 0.7 = Fa x 1.0

4.9N = Fa


The reading on the Newton meter R will be 2.1N

The reading on Newton meter Lwill be 4.9N