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Consider the expression
2 \pi \sqrt{(l)/(g)}.

where ℓ is length and g is gravitational acceleration in units of length divided by time squared.
Evaluate its units.
1. s²
2.
((s)/(m))^2
3.
((m)/(s))^2
4.
(m)/(s)
5. s
6. m²
7. m
8.
(s)/(m)

User Akhil K C
by
5.6k points

2 Answers

3 votes

Final answer:

The expression 2π√(l/g) has units of 2π(l/g)^(1/2).

Step-by-step explanation:

The given expression is 2π√(l/g), where ℓ represents length and g represents gravitational acceleration in units of length divided by time squared. To evaluate the units of the expression, we need to break it down step by step:

The square root of a unit is equal to the unit raised to the power of 1/2. Therefore, the square root of (l/g) would have units of (l/g)^(1/2). Multiplying 2π by (l/g)^(1/2) would result in units of 2π(l/g)^(1/2). Finally, the (√) symbol represents the square root, so (√(l/g)) would have units of (l/g)^(1/2). Therefore, the expression 2π√(l/g) has units of 2π(l/g)^(1/2).

User Indextwo
by
5.8k points
6 votes

Answer:

Step-by-step explanation:

lets start from the expression
2\pi \sqrt{(l)/(g) }, first remember that
2\pi is a constant with no units, so we do not need to consider it for this problem, so lets just think about
(l)/(g)

Next lets replace the units, l is the length which is represented in metters by international units system

g is the gravitational constants, so the units are lengt divided by time squared, since time is in seconds we have
(m)/(s^(2) )

so pluging that into our formula we have
\sqrt{(m)/((m)/(s^(2) ) ) }

Now see we are dividing by a fraction, remember that to divide by a fraction is the same as to multiply by the reciprocal fraction, so we just flip the fraction and we get
\sqrt{m*(s^(2) )/(m) }

then if we perform the multiplication we have inside the radical we get
\sqrt{(m*s^(2) )/(m) }

Then since we are multiplying and dividing by m, the m's just cancel and we have
\sqrt{s^(2) }

Now remember that square and square root are inverse operations, so they cancel each other and we are left with just
s, which means seconds, so the answer would be option 5

hope that helps, good bye :)

User Meir Tseitlin
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5.0k points