Someone please help me answer these

Soloha48 [4]

I think it’s C b/c it works for me

3 0

2 years ago

Write about the similarities and differences between kinetic and potential energy. Include specific, real world example in your

lord [1]

Answer:

Energy is transformed from potential to kinetic and vice versa

Explanation:

The energy is transformed from mechanical to kinetic energy when the object changes its position with respect to a reference point, where it loses height but increases its speed. When the object is at maximum height with respect to a reference point, it will have its maximum potential energy value. When the object passes through the reference point it will have potential energy equal to zero, but this energy will become kinetic energy.

The most characteristic and real example is that of a pendulum at one end, as can be seen in the attached image.

When the pendulum is located at the top end, as shown in Figure 1, at that point the maximum potential energy will be held. Then the pendulum is released and when it passes through the reference point and its height is zero, with respect to that point, all potential energy will have become kinetic energy in the same way at this point the maximum speed of the pendulum will be set.

8 0

3 years ago

A flywheel turns through 40 rev as it slows from an angular speed of 1.5 rad/s to a stop.

Lynna [10]

Answer:

-0.0047 rad/s²

335.103 seconds

99.18 seconds

Explanation:

$\omega_f$ = Final angular velocity

$\omega_i$ = Initial angular velocity = 1.5 ra/s

$\alpha$ = Angular acceleration

$\theta$ = Angle of rotation = 40 rev

t = Time taken

Equation of rotational motion

$\omega_f^2-\omega_i^2=2\alpha \theta\\\Rightarrow \alpha=\frac{\omega_f^2-\omega_i^2}{2\theta}\\\Rightarrow \alpha=\frac{0^2-1.5^2}{2\times 2\pi \times 40}\\\Rightarrow \alpha=-0.0047\ rad/s^2$

Acceleration while slowing down is -0.0047 rad/s²

$t=\frac{\omega_f-\omega_i}{\alpha}\\\Rightarrow t=\frac{0-1.5}{-0.0047}\\\Rightarrow t=335.103\ s$

Time taken to slow down is 335.103 seconds

$\theta=\omega_it+\frac{1}{2}\alpha t^2\\\Rightarrow 20\times 2\pi=1.5\times t+\frac{1}{2}\times -0.0047\times t^2\\\Rightarrow 0.00235t^2-1.5t+125.66=0$

Solving the equation

$t=\frac{-\left(-1.5\right)+\sqrt{\left(-1.5\right)^2-4\cdot \:0.00235\cdot \:125.66}}{2\cdot \:0.00235}, \frac{-\left(-1.5\right)-\sqrt{\left(-1.5\right)^2-4\cdot \:0.00235\cdot \:125.66}}{2\cdot \:0.00235}\\\Rightarrow t=539.11, 99.18\ s$

The time required for it to complete the first 20 is 99.18 seconds as 539.11>335.103

4 0

2 years ago

A housekeeper is cleaning the kitchen and decides to to use a ladder to reach a top shelf. As he/she is cleaning he/she is start

pshichka [43]

The amount of gravitational force between both objects will be the same.

The magnitude of the Earth's gravitational force exerted on the housekeeper is calculated by applying Newton's second law of motion;

F = mg

where;

m is the mass of the housekeeper

g is acceleration due to gravity

According to Newton's third law of motion, action and reaction are equal and opposite.

The force exerted on the housekeeper by the Earth is equal in magnitude to the force exerted on the Earth by the housekeeper.

$F_{H} = - F_{E}$

The two forces are equal in magnitude but opposite in direction.

Thus, the correct option is " the amount of gravitational force between both objects will be the same"

The missing part of the question is below:

a. the Earth exerts the largest amount of gravitational force

b. the housekeeper exerts the largest amount of gravitational force

c. the amount of gravitational force between both objects will be the same

Learn more about Newton's third law of motion here: brainly.com/question/15507

3 0

1 year ago

A 4.5cm tall object is placed 28cm in front of a spherical mirror. It is to produce a virtual image that is upright and 3.5cm ta

Ostrovityanka [42]

A- convex B- 21.77cm C- 0.01022cm D- 0.02044cm

7 0

3 years ago