Explanation:
F = 20N m= m1 a=10m/s²
m=m2 a=5m/s²
F = ma
<u>for the first one</u><u>:</u><u> </u>
f=m1 × a
20 = m1 ×10
20=10m1
m1=20/10
m1=2
<u>for</u><u> </u><u>the</u><u> </u><u>second</u><u> </u><u>one</u><u> </u><u>:</u>
f=m2×a
20=m2×5
m2= 20/5
m2= 4
since F=ma
F=(m1+m2) ×a
F =(4+2)×a
F =6×a
F=20(from the question above )
20=6×a
a=20/6
a=3.33
Answer:
Potential energy increases.
Explanation:
We know that the direction of electric field is from positive to negative charge. As the proton has the positive charge so if it moves in the direction opposite of electric field, it means that the positive charge will move towards the positive region. As the positive charge is attracted towards negative and repelled by the positive charge. So the work done will be negative in bringing the positive charge towards the positive region of the field and potential energy increases in the direction opposite to electric field. As the potential energy decreases in the direction of electric field.
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.
Answer:
Explanation:
18 km / h
= 300 m / min
12 km / h = 200 m / min
distance travelled in 200 minutes = 300 x 200 = 60000 m
distance travelled in 50 minute in return journey = 200 x 50 = 10000 m
total distance travelled = 70000 m
total time = 250 minute
speed = 70000 / 250
= 280 m / min
= 16.8 km / h
Total displacement = 60000 - 10000 = 50000 m
total time = 250 min
velocity = 50000 / 250
= 200 m / min
= 12 km / h