This drag force is always opposite to the object's motion, and unlike friction between solid surfaces, the drag force increases as the object moves faster.
The velocity of the girl is -4.8 m/s.
Using the principle of conservation of linear momentum, The total momentum of bodies before and after collision is constant. Since the two objects are stationary, the initial momentum of each body is zero.
Thus;
0 = (80 × 3) + (50 × v)
0 = 240 + 50 v
-240 = 50 v
v = -240/50
v = -4.8 m/s
Note that the negative sign shows that the velocity of the girl is in opposite direction that that of the girl.
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The water outflow in 30 secs through 200 mm of the capillary tube is mathematically given as

<h3>What is the water outflow in 30 secs through 200 mm of the capillary tube?</h3>

Generally, the equation for Rate of flow of Liquid is mathematically given as

$$
Where dP is pressure difference r is the radius
is the viscosity of water
L is the length of the pipe


In $30s the quantity that flows out of the tube

In conclusion, the quantity that flows out of the tube

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One should check the battery every week.
A battery if not maintained properly can cause it to die earlier or get damaged. The reasons why should the battery be checked regularly is that due to improper management of the battery and also the weather conditions, the battery usually gets corroded easily and the battery won't be able to work properly.
The connections must be checked properly so that the battery gets charged properly and should not die while driving.