All categories

2 years ago

Someone please help me, I know I already asked a question please don't think I not smart, but

Physics

1 answer:

Anastaziya [24]2 years ago

7 0

Answer:

PE is related to the ability to do work, If an item is sitting on a shelf

it has potential energy relative to its position on the floor, However, if the object were to fall it would hit the floor with a KE equal to the PE that it had sitting on the shelf.

Sounds are caused by compressional waves in the air - when a piano key is struck or a TV is turned on, then compressional waves are produced in the surrounding air due to a disturbance. The human ear recognizes the disturbed air as due to the object that created the disturbance.

You might be interested in

A particle moves along the x axis. It is initially at the position 0.180 m, moving with velocity 0.060 m/s and acceleration -0.3

shusha [124]

Answer:

$x_2 = -2.3356$

$v = -1.384 \ m/s$

Explanation:

From the question we are told that

The initial position of the particle is $x_1 = 0.180 \ m$

The initial velocity of the particle is $u = 0.060 \ m/s$

The acceleration is $a = -0.380 \ m/s^2$

The time duration is $t = 3.80 \ s$

Generally from kinematic equation

$v = u + at$

=> $v = 0.060 + (-0.380 * 3.80)$

=> $v = -1.384 \ m/s$

Generally from kinematic equation

$v^2 = u^2 + 2as$

Here s is the distance covered by the particle, so

$(-1.384)^2 = (0.060)^2 + 2(-0.380)* s$

=> $s = -2.5156 \ m$

Generally the final position of the particle is

$x_2 = x_1 + s$

=> $x_2 = 0.180 + (-2.5156)$

=> $x_2 = -2.3356$

6 0

3 years ago

The flywheel of a steam engine runs with a constant angular velocity of 190 rev/min. When steam is shut off, the friction of the

Ivanshal [37]

Answer:

(a) $\alpha = - 1.32\ rev/m^{2}$

(b) $\theta = 13674\ rev$

(d) $a = 22.458\ m/s^{2}$

Solution:

As per the question:

Angular velocity, $\omega = 190\ rev/min$

Time taken by the wheel to stop, t = 2.4 h = $2.4\times 60 = 144\ min$

Distance from the axis, R = 38 cm = 0.38 m

Now,

(a) To calculate the constant angular velocity, suing Kinematic eqn for rotational motion:

$\omega' = \omega + \alpha t$

$omega'$ = final angular velocity

$\omega$ = initial angular velocity

$\alpha$ = angular acceleration

Now,

$0 = 190 + \alpha \times 144$

$\alpha = - 1.32\ rev/m^{2}$

Now,

(b) The no. of revolutions is given by:

$\omega'^{2} = \omega^{2} + 2\alpha \theta$

$0 = 190^{2} + 2\times (- 1.32) \theta$

$\theta = 13674\ rev$

(c) Tangential component does not depend on instantaneous angular velocity but depends on radius and angular acceleration:

$\alpha_{tan} = 0.38\times 1.32\times \frac{2\pi}{3600} = 8.75\times 10^{- 4}\ m/s^{2}$

(d) The radial acceleration is given by:

$\alpha_{R} = R\omega^{2} = 0.32(80\times \frac{2\pi}{60})^{2} = 22.45\ rad/s$

Linear acceleration is given by:

$a = \sqrt{\alpha_{R}^{2} + \alpha_{tan}^{2}}$

$a = \sqrt{22.45^{2} + (8.75\times 10^{- 4})^{2}} = 22.458\ m/s^{2}$

5 0

3 years ago

The current in a hair dryer measures 11 amps. The resistance of the hair dryer is 12 ohms. What is the voltage?

Valentin [98]

Voltage is given by the formula

V = IR (Ohms law)

where V is the Voltage

I is the current

and R is the Resistance

Here it is given that the current is I=11

Resistance is R =12

so plugging this in the formula

V = IR

V= 11 * 12

V= 132 Volts

So the Voltage for the given dryer is 132 Volts

8 0

4 years ago

When a box of chocolate bars is in mechanical equilibrium, what can be correctly said about all the forces that act on it?

rjkz [21]

Answer:

All the forces are opposite and equal and will give net force zero.

Explanation:

Mechanical equilibrium is the equilibrium in which the total force on the system is zero means the system is neither accelerated nor any kind of torque on the system.

The mechanical system can also be defined as the equal forces are applied in opposite direction in a system which cancels out all the forces, will give net force zero.

Therefore, when a box of chocolate bars is in mechanical equilibrium all the forces in this system are equal and the opposite which balances each other will give net force zero.

3 0

4 years ago

What is the relationship between magnetism and potential and kinetic energy

vaieri [72.5K]

Check out Faraday's Law

5 0

3 years ago