# MCAT Physics Thought Question...

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#### chandler742

##### Senior Member
7+ Year Member
15+ Year Member

Here is another question.

What is 1 light year approximately?

A) 1 x 10 ^10 secs
B) 1 x 10 ^10 meters
C) 1 x 10 ^15 secs
D) 1 x 10 ^ 15 meters

(HINT: Don't forget on the MCAT you must know how to
approximate exponents)

#### Mr. Z

##### Senior Member
7+ Year Member
15+ Year Member
365 x 24hr/dayx3600sec/hr = 3.2x10^8 sec in a year

(3.2x10^8) x (3x10^8) = 9x10^16 or ~1x10^15

7+ Year Member
15+ Year Member
I second that.

10+ Year Member
15+ Year Member
amen

#### dark_scientist

##### Full Member
15+ Year Member
The time is 3.2e7 not 3.2e8, which when multiplied by the speed of light (3e8) is 9e15 = ~1e16, which is not one of the answer choices. Did I do a calculation wrong or is the answer choice supposed to be 1e16?

#### chandler742

##### Senior Member
7+ Year Member
15+ Year Member
right. Good job, guys.

As an aside, this appeared on my MCAT as a free response question. I fabricated the wrong values, but the meters and sec were scattered as choices.