All categories

2 years ago

A ball is falling after rolling off a tall roof The ball has what type of energy.

Physics

1 answer:

CaHeK987 [17]2 years ago

3 0

Answer:

Linear and rotational Kinetic Energy + Gravitational potential energy

Explanation:

The ball rolls off a tall roof and starts falling.

Let us first consider the potential energy or more specifically gravitational potential energy ( $mgh$ ; $m$ = mass of the ball, $g$ = acceleration due to gravity, $h$ = height of the roof). This energy comes because someone or something had to do work to take the ball to the top of the roof against the force of gravity. The potential energy is naturally maximum at the top and minimum when the ball finally reaches the ground.

Now, the ball starts to roll and falls off the roof. It shall continue rotating because of inertia (Newton's first law). This contributes to the rotational kinetic energy ( $\frac{1}{2}I\omega^2$ ; $I$ =moment of inertia of the ball & $\omega$ = angular velocity).

Finally comes the linear kinetic energy or simply, kinetic energy ( $\frac{1}{2}mv^2$ ) which is caused due to the velocity $v$ of the ball.

You might be interested in

A dolphin can swim at a constant speed of 12.5 m/s. How

myrzilka [38]

Answer:

$\boxed {\tt 3.6 \ seconds}$

Explanation:

Time can be found by dividing the distance by the speed.

$t=\frac{d}{s}$

The distance is 45 meters and the speed is 12.5 meters per second.

$d= 45 \ m \\s= 12.5 \ m/s$

$t=\frac{45 \ m}{12.5 \ m/s}$

Divide. Note that the meters, or "m" will cancel each other out.

$t=\frac{45 }{12.5 \ s}$

$t=3.6 \ s$

It will take the dolphin 3.6 seconds to swim a distance of 45 meters are 12.5 meters per second.

6 0

2 years ago

Read 2 more answers

The efficiency of a machine increases as the temperature inside _____ relative to the temperature outside.

Archy [21]

The answer is increases

5 0

3 years ago

Read 2 more answers

Water from a vertical pipe emerges as a 10-cm-diameter cylinder and falls straight down 7.5 m into a bucket. The water exits the

cupoosta [38]

The diameter of the column of the water as it hits the bucket is 4.04 cm

The equation of continuity occurs in the fluid system and it asserts that the inflow and the outflow of the volume rate at the inlet and at the outlet of the system are equal.

By using the kinematics equation to determine the speed of the water in the bucket and applying the equation of continuity to estimate the diameter of the column, we have the following;

Using the kinematics equation:

$\mathbf{v_f ^2 = v_i^2 + 2gh}$

$\mathbf{v_f ^2 =(2.0)^2 + 2\times 9.8 \times 7.5}$

$\mathbf{v_f ^2 =151 m/s}$

$\mathbf{v_f =\sqrt{151 m/s}}$

$\mathbf{v_f =12.29 \ m/s}$

From the equation of continuity:

$\mathbf{A_iV_i = A_fV_f}$

$\mathbf{\pi r^2_iV_i = \pi r^2_fV_f}$

$\mathbf{ r^2_iV_i = r^2_fV_f}$

$\mathbf{ (\dfrac{10}{2})^2\times 2.0 = r_f^2 \times 12.29}$

$\mathbf{ 50 = 12.29 \times r_f^2}$

$\mathbf{ r_f= \sqrt{\dfrac{50}{12.29} }}$

$\mathbf{ V_f= 2.02 \ cm }$

Since diameter = 2r;

∴

The diameter of the column of the water is:

= 2(2.02) cm

= 4.04 cm

Learn more about the equation of continuity here:

brainly.com/question/10822213

6 0

2 years ago

A wheel has a radius of r = 2.0 m and it rolls down a smooth incline. The height of the incline is h = 8.0 m . What is the angul

zepelin [54]

The angular velocity of the wheel at the bottom of the incline is 4.429 rad/sec

The angular velocity (ω) of an object is the rate at which the object's angle position is changing in relation to time.

For a wheel attached to an incline angle, the angular velocity can be computed by considering the conservation of energy theorem.

As such the total kinetic energy (K.E) and rotational kinetic energy (R.K.E) at a point is equal to the total potential energy (P.E) at the other point.

i.e.

P.E = K.E + R.K.E

$\mathbf{mgh = \dfrac{1}{2}m(r \times \omega)^2 + \dfrac{1}{2}\times I \times \omega^2}$