Gasoline comes from petroleum, which is made from ancient living things. Petroleum, therefore, contains a type of _____ energy.
2 answers:
You might be interested in
Answer:
0.0928km/min (4dp)
Explanation:
To find the jogger's speed in km per minute, we just need to divide the number of km jogged by the time in minutes it took to jog that distance. This will give us the distance they jogged every minute which is their speed.
4km in 32 minutes:
4/32 = 0.125km/min
2km in 22 minutes:
2/22 = 0.091 (3dp)km/min
1km in 16 minutes:
0.0625km/min
Now to find the average speed of these 3 speeds, we just add them all together and divide by how many values there are (3 values).
Average (mean) =
Average = 0.2785/3
Average speed of jogger = 0.0928 (4dp) km/min
Hope this helped!
Answer:
The pressure on the ground is about 9779.5 Pascal.
The pressure can be reduced by distributing the weight over a larger area using, for example, a thin plate with an area larger than the circular area of the barrel's bottom side. See more details further below.
Explanation:
Start with the formula for pressure
(pressure P) = (Force F) / (Area A)
In order to determine the pressure the barrel exerts on the floor area, we need the calculate the its weight first
where m is the mass of the barrel and g the gravitational acceleration. We can estimate this mass using the volume of a cylinder with radius 30 cm and height 1m, the density of the water, and the assumption that the container mass is negligible:
The density of water is 997 kg/m^3, so the mass of the barrel is:
and so the weight is
and so the pressure is
This answers the first part of the question.
The second part of the question asks for ways to reduce the above pressure without changing the amount of water. Since the pressure is directly proportional to the weight (determined by the water) and indirectly proportional to the area, changing the area offers itself here. Specifically, we could insert a thin plate (of negligible additional weight) to spread the weight of the barrel over a larger area. Alternatively, the barrel could be reshaped (if this is allowed) into one with a larger diameter (and smaller height), which would achieve a reduction of the pressure.