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Question
A block of iron of mass 7.5 kg and of dimensions 12 cm × 8 cm × 10 cm is kept on a table top on its base of side 12 cm × 8 cm.
Calculate:
- Thrust and
- Pressure exerted on the table top
Take 1 kgf = 10 N.
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Solution
1 kgf = 10 N
∴ g = 10 ms-2
1) Thrust is
F = mg
= 7.5 kg × 10
= 75 N
2) Pressure is force per area.
∴ P = `"F"/"A"_"base"`
= `75/(12 xx 10^-2 xx 8 xx 10^-2)`
∴ P = 7812.5 Pa
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