Respuesta :
Answer:
57 kg
Explanation:
Mass of seesaw = 20 kg
Length of seesaw = 4 m
Mass of child on the longer end = 30 kg
The weight of the seesaw acts at the center i.e. 2m
The algebraic sum of moments of all forces about any point is zero, hence, using the fulcrum as the reference point:
[x * 9.8* 1.5] - [20 * 9.8* (2.5 - 2)] - [30 * 9.8 * 2.5] = 0
=> 14.7x = (20*9.8*0.5) + 735
14.7x = 98 + 735
14.7x = 833
=> x = 833/14.7
x = 57 kg
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The mass a person at the other end is 57 kg
Calculation of the mass;
Since
Mass of seesaw = 20 kg
Length of seesaw = 4 m
Mass of child on the longer end = 30 kg
The weight of the seesaw acts at the center i.e. 2m
So, here we assume the mass be x
Now the following equation should be applied.
[x * 9.8* 1.5] - [20 * 9.8* (2.5 - 2)] - [30 * 9.8 * 2.5] = 0
14.7x = (20*9.8*0.5) + 735
14.7x = 98 + 735
14.7x = 833
x = 833/14.7
x = 57 kg
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