The first thing that needs to be done is to find everything in the same units. 12 hours becomes 43200 seconds. Then find the distance traveled by light in that amount of time. Using the formula v=d/s, manipulate it so it looks like d=v*s. Then plug in the values: d=(3x10^8)*43200, d=1.3x10^13m. But you need to find this in kilometers. To do this, simply divide your answer by one thousand. Thus, a laser beam would travel 1.3x10^10 kilometers in 12 hours.
<span>When air resistance acts, acceleration during a fall will be less than g because air resistance affects the motion of the falling objects by slowing it down. Air resistance depends on two important factors - the speed of the object and its surface area. Increasing the surface area of an object decreases its speed.</span>
Answer:
= 3.869 × 10^-6 J/m³
Explanation:
Intensity is given as W/m^2 which is equivalent to J/ (s*m^2)
Speed of light is 2.99792 × 10^8 m/s.
Therefore;
Electromagnetic energy per cubic meter = Intensity/speed of light
= 1160 J/ (s*m³)/ 2.99792 × 10^8 m/s.
<u>= 3.869 × 10^-6 J/m³</u>
Answer:
Yes, the race car driver needs a faster reaction time than someone driving in a school zone.
Explanation.
For the sake of argument, let us consider
(i) a person driving at 35 mph in a school zone (as a normal driver);
(ii) a person driving at 60 mph in a school zone (as a racing driver).
Suppose a blind pedestrian crosses the road 0.1 miles (about 500 feet) in front of the driver.
The time before the normal driver hits the pedestrian is
(0.1 /35)*3600 = 10.3 seconds.
The time before the racing driver hits the pedestrian is
(0.1/60)*3600 = 6 seconds.
Because a reaction time of 6 seconds may be insufficient to avoid hitting the pedestrian, the racing driver needs a faster reaction time than the normal driver.
