Average speed is defined as the ratio of total distance covered in total given time
here we know that total distance that man moved is
so total distance is
now here total time of the motion is
total time will be given as
now by above formula
so his average speed is 30 km/h
<h3>Reducing Surface Area.</h3>
If the surface area becomes smaller, the pressure becomes larger.
Answer:
ax = 6.43m/s²
Explanation:
The acceleration is the time derivative of the velocity function ax = dvx(t)/dt
We have been given the velocity function v(t) and also the velocity v = 12.0m/s and we are requested to calculate the acceleration at this time which we don't know.
So the first step is to calculate the time at which the velocity =12.0m/s and with this time calculate the acceleration. Detailed solution can be found in the attachment below.
Answer:
Global dependence on fossil fuels has associated social costs.
Explanation:
Increased dependence on fossil fuels reduces their availability. When the demand is high and the availability is low, the price rises. Not every nation would then be able to afford buying fossil fuels at such high costs.
Developing and underdeveloped countries would then be left behind and only the wealthy nations would be able to afford fossil fuel purchase. This would be the immediate impact of global dependence on fossil fuels.
Fossil fuels are mainly coal, petroleum and natural gas. Since fossil fuels are non-renewable in nature over exploitation may lead to fossil fuels getting exhausted.
Answer:
Hipparchus was an ancient Greek who classified stars based on the brightness in 129 B.C. He grouped the brightest stars and ranked them 1 (first magnitude) and dimmest stars as 6 (sixth magnitude). Thus, the smaller numbers indicated brighter stars. Now, the scale extends in negative axis as well. More the negative number, brighter is the star. For example, Sun has magnitude -26.74.
This the apparent magnitude which means the classification is based on the brightness of the star as it appears from the Earth.