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3 years ago

How much kinetic energy does an object have that is moving at a rate of 30 m/s and has a mass of 4000 kg ?

Physics

1 answer:

DaniilM [7]3 years ago

3 0

Answer:

K = 1800 kJ

Explanation:

Given that,

The speed of the object, v = 30 m/s

Mass of the object, m = 4000 kg

We need to find the kinetic energy of the object. The formula for the kinetic energy is given by :

$K=\dfrac{1}{2}mv^2\\\\K=\dfrac{1}{2}\times 4000\times 30^2\\\\K=1800000\\\\or\\\\K=1800\ kJ$

So, the required kinetic energy is equal to 1800 kJ.

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Explanation:

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So, V = $\frac{10^{-3}}{19.3 \times 10^{3} kg/m^{3}}$

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R = $\rho \frac{l}{A}$

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4 0

3 years ago

A(n) 10.1 g bullet is fired into a(n) 2.41 kg ballistic pendulum and becomes embedded in it. The acceleration of gravity is 9.8

fomenos

Answer:

$v = 186.90\,\frac{m}{s}$

Explanation:

The motion of ballistic pendulum is modelled by the appropriate use of the Principle of Energy Conservation:

$\frac{1}{2}\cdot (m_{p}+m_{b})\cdot v^{2} = (m_{p}+m_{b})\cdot g \cdot h$

The final velocity of the system formed by the ballistic pendulum and the bullet is:

$v = \sqrt{2\cdot g\cdot h}$

$v = \sqrt{2\cdot (9.807\,\frac{m}{s^{2}} )\cdot (0.031\,m)}$

$v\approx 0.78\,\frac{m}{s}$

Initial velocity of the bullet can be calculated from the expression derived of the Principle of Momentum:

$(0.0101\,kg)\cdot v = (2.41\,kg + 0.0101\,kg)\cdot (0.78\,\frac{m}{s} )$

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5 0

3 years ago

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Answer:

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A flying aeroplane has potential energy has it flies above the ground level. And since the aeroplane is flying motion is associated with it and thus possesses kinetic energy. Hence a flying aeroplane has both potential and kinetic energ

Explanation:

5 0

3 years ago

Write an expression for the potential energy UD of a particle when it is at a distance D from the force center, in terms of B an

nadezda [96]

Answer:

E+mc+UD-3

Explanation:

7 0

4 years ago

A force acting over a large area will exert less pressure per square inch than the same force acting over a smaller area.

babunello [35]

Answer:

True

Explanation:

Pressure is defined as:

$p=\frac{F}{A}$

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$p\propto \frac{1}{A}$

this means that, assuming that the forces in the two situations (which have same magnitude) are both applied perpendicular to the surface, the force exerted over the smaller area will exert a greater pressure. Hence, the statement"

<em>"A force acting over a large area will exert less pressure per square inch than the same force acting over a smaller area"</em>

is true.

8 0

3 years ago