Answer:
15.75 cm
Explanation:
focal length of convex lens, f = + 9 cm
position of object, u = - 21 cm
Let the distance of image is v.
Use lens equation
1 / f = 1 / v - 1 / u
1 / 9 = 1 / v + 1 / 21
1 / v = 1 / 9 - 1 / 21 = (21 - 9) / (21 x 9)
1 / v = 12 / 189
v = 15.75 cm
Answer:
c. No. An equation may have consistent units but still be numerically invaid.
Explanation:
For an equation to be corrected, it should have consistent units and also be numerically correct.
Most equation are of the form;
(Actual quantity) = (dimensionless constant) × (dimensionally correct quantity)
From the above, without the dimensionless constant the equation would be numerically wrong.
For example; Kinetic energy equation.
KE = 0.5(mv^2)
Without the dimensionless constant '0.5' the equation would be dimensionally correct but numerically wrong.
Most likely the answer is B.
Explanation:
<h2>
<em>The </em><em>S. </em><em>I. </em><em> </em><em>unit </em><em>of </em><em>momentum </em><em>is </em><em>Kg. </em><em>m/</em><em>s</em><em>e</em><em>c</em></h2>
<em>hope </em><em>it </em><em>helps </em><em>you </em>
