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1. hello how to do this please help me3. The relationship between four physical quantities is given by the equation P = Q - RS.
Given that the equation is homogeneous, which of the following statements must be correct?

A. P,Q, R and S all have the same units.

B. P,Q, R and S are all scalar quantities.

C. The product RS has the same units as P and Q,

D. The product RS is numerically equal to Q - P.
2. (Original post by KULER)
hello how to do this please help me3. The relationship between four physical quantities is given by the equation P = Q - RS.
Given that the equation is homogeneous, which of the following statements must be correct?

A. P,Q, R and S all have the same units.

B. P,Q, R and S are all scalar quantities.

C. The product RS has the same units as P and Q,

D. The product RS is numerically equal to Q - P.
In an homogeneous equation, the units (dimensions) on the LHS must be the same as those on the RHS.
In an equation you cannot add or subtract quantities that do not have the same units. You cannot subtract a kilogram from a second.
The equation must also be arithmetically correct. The LHS must numerically equal the RHS.
You should now be able to identify which statements are correct.

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