## maparicio 2 years ago In air at 20 , sound travels at a constant speed of 344 . The light speed is equal to 299792458 . The light year is defined as the distance light travels in 1 year. Use this information to determine how many meters there are in 1 light year. Also, How many meters does light travel in 1 nanosecond?

1. 3psilon

Use dimensional analysis We'll call the speed of light $3x10^{8}$ so.$\frac{ 3x10^{8}meters }{ 1 \sec }*\frac{ 60 \sec }{ 1 \min} *\frac{ 60 \min }{ 1 hr }*\frac{ 24 hrs }{ 1 day }$

2. 3psilon

Every thing should cancel out but meters and days. Then just multiply by 365 days to get how many meters it travels in a year

3. maparicio

Thanks the answer is 9.46 x 10^15 m

4. 3psilon

np :)

5. maparicio

Do you know How many meters does light travel in 1 nanosecond?