A ball falling through the air has--------

A 6.7kg object moves with a velocity of 8m/s. What's its kinetic energy?

Snezhnost [94]

Given parameters:

Mass of object = 6.7kg

Velocity = 8m/s

Unknown parameter:

Kinetic energy = ?

Energy is defined as the ability to do work. There are two forms of energy;

Kinetic and potential energy.

Kinetic energy is the energy due to the motion of a body. Whereas, potential energy is the energy due to the position of a body usually at rest.

Kinetic energy is mathematically expressed as;

Kinetic energy = $\frac{1}{2} m v^{2}$

where m is the mass of the body

v is the velocity of the body

Since we have been given both mass and velocity, input the parameter to solve for the unknown;

Kinetic energy = $\frac{1}{2}$ x 6.7 x 8² = 214.4‬J

So the kinetic energy of the body is 214.4‬J

3 0

3 years ago

Which statement best describes frustration?

wlad13 [49]

C. when you can't achieve your goal due to events beyond your control

5 0

3 years ago

An incident on route 12 summary?I need to describe what happens in the book in a short summary can anyone help?

Serga [27]

Answer: An Incident on Route 12 is presented here in a high quality paperback edition. This popular classic work by James H. Schmitz is in the English language, and may not include graphics or images from the original edition.

Explanation: I HOPE THAT HELPED

5 0

3 years ago

a 75 kg man is standing at rest on ice while holding a 4kg ball. if the man throws the ball at a velocity of 3.50 m/s forward, w

AysviL [449]

Answer:

His resulting velocity will be 0.187 m/s backwards.

Explanation:

Given:

Mass of the man is, $M=75\ kg$

Mass of the ball is, $m=4\ kg$

Initial velocity of the man is, $u_m=0\ m/s(rest)$

Initial velocity of the ball is, $u_b=0\ m/s(rest)$

Final velocity of the ball is, $v_b=3.50\ m/s$

Final velocity of the man is, $v_m=?\ m/s$

In order to solve this problem, we apply law of conservation of momentum.

It states that sum of initial momentum is equal to the sum of final momentum.

Momentum is the product of mass and velocity.

Initial momentum = Initial momentum of man and ball

Initial momentum = $Mu_m+mu_b=75\times 0+4\times 0 =0\ Nm$

Final momentum = Final momentum of man and ball

Final momentum = $Mv_m+mv_b=75\times v_m+4\times 3.50 =75v_m+14$

Now, initial momentum = final momentum

$0=75v_m+14\\\\75v_m=-14\\\\v_m=\frac{-14}{75}\\\\v_m=-0.187\ m/s$

The negative sign implies backward motion of the man.

Therefore, his resulting velocity is 0.187 m/s backwards.

3 0

3 years ago

A power cycle operates between hot and cold reservoirs at 1200 K and 300 K, respectively. At steady state the cycle develops a p

GenaCL600 [577]

Answer:

Explanation:

a ) Thermal efficiency = work output / heat input

= .38 MW / 1 MW = .38

OR 38%

Heat rejected at cold reservoir = heat input - work output

1 MW - .38 MW

= 0.62 MW.

b ) For reversible power output

efficiency = T₂ - T₁ / T₂ ; T₂ is temperature of hot reservoir and T₁ is temperature of cold reservoir.

= 1200 - 300 / 1200 = 900 / 1200

= .75

or 75%

rate at which heat is rejected

= 1 - .75 x 1

= .25 MW .

7 0

3 years ago