Answer:
ΔK = 2.45 J
Explanation:
a) Using the law of the conservation of the linear momentum:
Where:
Now:
Where 
is the mass of the car, 
is the initial velocity of the car, 
is the mass of train, 
is the final velocity of the car and 
is the final velocity of the train.
Replacing data:
Solving for :
Changed to cm/s, we get:
b) The kinetic energy K is calculated as:
K = 
where M is the mass and V is the velocity.
So, the initial K is:
And the final K is:
Finally, the change in the total kinetic energy is:
ΔK = Kf - Ki = 22.06 - 19.61 = 2.45 J
Well, the thing is: we don't really know, as we don't even know how many species there are on earth.
If we take a look at the estimates of <span>World Wide Fund for Nature, an organization that works toward combating species extinction, their estimates vary from 200 to 100 000 - but a probable number is 20 000 (d). </span>
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Answer:
The tension on the string is 2.353 N.
Explanation:
Given;
the speed of sound in air, v₀ = 343 m/s
then, the speed of sound on the string, v = 343 / 10 = 34.3 m/s
mass per unit length, m/l = μ = 0.002 kg/m
The speed of sound on the string is given as;
where;
T is the tension on the string
T = (34.3)²(0.002)
T = 2.353 N
Therefore, the tension on the string is 2.353 N.
The difference in the force exerted by the ground during a race between these two species is 259.25
<h3>What is force?</h3>
Forces are influences that can change the movement of an object. A force can change the velocity of an object with mass, i.e. accelerate it. Forces can also be described intuitively by pushing or pulling. A force has both magnitude and direction and is a vector quantity.
Force exerted by the lion:
Normal force = mg
170 = m × 9.8
m = 17.34 kg
Forward force = ma
= 17.34 × 10.0
= 173.4 N
Total force = Normal force + Forward force
Total force = 170 + 173.4
= 343.4 N
Force exerted by the man:
Normal force = mg
75 = m × 9.8
m = 7.65 kg
Forward force = ma
= 7.65 × 10.0
= 76.5 N
Total force = Normal force + Forward force
Total force = 7.65 + 76.5
= 84.15 N
The difference in the forces exerted by these species is:
343.4 N - 76.5 N = 259.25 N
To know more about force visit:
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Answer:
The kinetic energy of tennis ball is higher than that of baseball.
Explanation:
mass of baseball 
= 0.14 kg
velocity of baseball 
= 41 m/s
mass of tennis ball 
= 0.058 kg
velocity of tennis ball 
= 67 m/s
To find: the kinetic energy of baseball 
and tennis ball 
We know that the kinetic energy is given by the equation,
KE = 
the kinetic energy of baseball = 
= 
= 117.67 J
the kinetic energy of tennis ball = 
= 
= 130.181 J
Hence > , the kinetic energy of tennis ball is higher than that of baseball
