An electric iron connected to a 110 V source draws 9 A of current. How much heat (in joules) does it generate in a minute?

A man stands at the edge of a cliff and throws a rock downward with A speed of 12.0 m s . Sometimes later it strikes the ground

kvasek [131]

B) 48.0 m/s

We can actually start to solve the problem from B for simplicity.

The motion of the rock is a uniformly accelerated motion (free fall), so we can find the final speed using the following suvat equation

$v^2 -u^2 = 2as$

where

$v$ is the final velocity

$u = 12.0$ is the initial velocity (positive since we take downward as positive direction)

$a=g=9.8 m/s^2$ is the acceleration of gravity

s = 110 m is the vertical displacement

Solving for v, we find the final velocity (and so, the speed of the rock at impact):

$v = \sqrt{u^2+2as}=\sqrt{12^2+2(9.8)(110)}=48.0 m/s$

A) 3.67 s

Now we can find the time of flight of the rock by using the following suvat equation

$v=u+at$

where

$v = 48.0$ is the final velocity at the moment of impact

$u = 12.0$ is the initial velocity

$a=g=9.8 m/s^2$ is the acceleration of gravity

t is the time it takes for the rock to reach the ground

And solving for t, we find

$t=\frac{v-u}{a}=\frac{48.0-12.0}{9.8}=3.67 s$

6 0

3 years ago

What happens when a roller coaster car moves down from the top of a hill?

VLD [36.1K]

When the roller coaster moves down from the top of the hill, all of its stored potential energy is converted into kinetic energy to move it and when it goes back up the hill it turns kinetic into potential.

3 0

3 years ago

Read 2 more answers

Please help on this one?

Setler79 [48]

I may be wrong but I think the answer is open. Hope this helps.

8 0

4 years ago

Plzzzz HELLPPPPPP!!!!

Rainbow [258]

?? what’s the topic

7 0

3 years ago

For a wavelength of 420 nm, a diffraction grating produces a bright fringe at an angle of 24°. For an unknown wavelength, the sa

Inessa [10]

Answer:

649.8420 nm

Explanation:

We have given $\Theta _1=24^{\circ} \ and\ \Theta _2=39^{\circ}$

$\lambda _1=420\ nm$ we have to find unknown wavelength that is $\lambda _2$

The condition for constructive interference is $dsin\Theta =n\lambda$

Where d is distance between slits $\Theta$ is angle of emergence and n is order of maxima

Using constructive interference equation

$dsin\Theta _1=n\lambda _1$ ---------eqn 1

$dsin\Theta _2=n\lambda _2$ ---------eqn 2

On dividing eqn 1 by eqn 2

$\frac{\lambda _1}{\lambda _2}=\frac{sin\Theta _1}{sin\Theta _2}$

$\frac{420}{\lambda _2}=\frac{sin24^{\circ}}{sin39^{\circ}}$

$\lambda _2=649.8420\ nm$

7 0

3 years ago