Kinetic Energy = 1/2 * mass * velocity^2
Mass = 0.1 kg
Velocity = 20 m/s
Kinetic energy = 1/2 * 0.1 * 20^2
Kinetic energy = 1/2 * 0.1 * 400
Kinetic energy = 20 J
Answer:
Time taken for car to stop = 0.89 seconds (Approx.)
Explanation:
Given:
Mass of car = 1100 kg
Speed of car = 15 m/s
Impact force = 185,000 N
Find:
Time taken for car to stop
Computation:
Change in momentum of car = M(v) - M(u)
Change in momentum of car = 1100(0) - 1100(15)
Change in momentum of car = -16,500
Time taken for car to stop = I Change in momentum of car I / Impact force
Time taken for car to stop = I-16,500I / 185,000
Time taken for car to stop = 0.89 seconds (Approx.)
Answer:
$1.26
Explanation:
Power =energy/ time
energy =powerxtime
energy =50x31x24=37200
=37.2kwh
1kwh =3.39
37.2kwh=3.39x37.2=126.108cent
=$1.26
Answer:
21.21 m/s
Explanation:
Let KE₁ represent the initial kinetic energy.
Let v₁ represent the initial velocity.
Let KE₂ represent the final kinetic energy.
Let v₂ represent the final velocity.
Next, the data obtained from the question:
Initial velocity (v₁) = 15 m/s
Initial kinetic Energy (KE₁) = E
Final final energy (KE₂) = double the initial kinetic energy = 2E
Final velocity (v₂) =?
Thus, the velocity (v₂) with which the car we travel in order to double it's kinetic energy can be obtained as follow:
KE = ½mv²
NOTE: Mass (m) = constant (since we are considering the same car)
KE₁/v₁² = KE₂/v₂²
E /15² = 2E/v₂²
E/225 = 2E/v₂²
Cross multiply
E × v₂² = 225 × 2E
E × v₂² = 450E
Divide both side by E
v₂² = 450E /E
v₂² = 450
Take the square root of both side.
v₂ = √450
v₂ = 21.21 m/s
Therefore, the car will travel at 21.21 m/s in order to double it's kinetic energy.
Answer:
Stable atom
Explanation:
A stable atom is one that has a balanced nuclear inter-particle force reaction as such the binding energy of a stable atom is sufficient to permanently keep the nucleus as one unit. Examples of a stable atom are the atoms of monoisotopic elements such as fluorine, sodium, iodine, gold, aluminium, and cobalt.
In a stable atom the expected number of proton, neutron, and electron are present while in an unstable atom or radioactive atom, there are more than the expected number of neutrons or protons, such that the internal energy of the nucleus is excessive and more than the binding energy, which can lead to radioactive decay.