Question

Physies 1301: College Physies Homework 1 1. The speed of light is now defined to be 2.99 7924 58 x 10 m/s. Express the speed of light to (a) three significant figures, (b) five significant figures, and (e) seven significant figures 2. Using your calculator, find, in scientific notation with appropriate rounding. (a) the value of (2.437 x 10X6.521110.37 x 10) and (b) the value of (3.14159 x 10 x27.01 x 10 234 x 10) 3. Suppose your hair grows at the rate of 1/32 inch per day. Find the rate at which it grows in nanometers per second. Since the distance between atoms in a molecule is on the order of 0.1 nm your answer suggests how rapidly atoms are assembled in this protein synthesis. 4. The speed of light is about 3.00x 10 m/s. Convert this figure to miles per hour. 5. A house is 50.0 ft long and 26 ft wide and has 8.0-ft-high ceilings. What is the volume of the interior of the house in cubic meters and in cubic centimeters? (Volume length x width x height) 6. Two points in a rectangular coordinate system have the coordinates (5.0, 3.0) and (-3.0,4.0) where the units are centimeters, Determine the distance between these points 7. For the triangle shown in Figure below, what are (a) the length of the unknown side, (b) the tangent of 8, and (c) the sine of p? 6,00 m 9.00 m 8. A ladder 9.00 m long leans against the side of a building. If the ladder is inclined at an angle of 75.0° to the horizontal, what is the horizontal distance from the bottom of the ladder to the building? 9. A surveyor measures the distance across a straight river by the following method: Starting directly across from a tree on the opposite bank, he walks 100 m along the riverbank to establish a baseline. Then he sights across to the tree. The angle from his baseline to the tree is 35,.0°. How wide is the river?

Answer 1

C = 2.99792458 times 10^8 m/s 3 - significant figures 2.99 times 10^8 m/s 5 - significant figures 2.9979 times 10^8 m/s 7 - significant figures 2.997924 times 10^8 m/s this is a) 2.437 times 10^4 times 6.5211 times 10^9 times 5.37 times 10^4 = 2.96 times 10^9 b) 3.1459 times 10^2 times 27.01 times 10^4 times 1.234 times 10^4 = 68.76 times 10^2 1/32 inch/day = 1/32 times 2.54 times 10^-2 times 10^+ 9/24 times 3600 nm/sec = 9.187 nm/s C = 3 times 10^8 m/s = 3 times 10^8 times 0.0006213 miles/(1/3600) hr = 3 times 6.213 times 10^4 times 3600 mil/hr = 67100.4 times 10^4 miles/hr \r\n volume = 50 times 26 times 8 ft^3 = 50 times 26 times 8 times (0.305)^3 m^3 = 295.075 m^3 = 295.075 times 10^+ 6 cm^3 distance = squareroot (5 + 3)^2 + (3 - 4)^2 = squareroot 8^2 + 1^2 = squareroot 65 cm