Force = mass x acceleration

Use the exact values you enter to make later calculations. Jack and Jill are on two different floors of their high rise office b

erastovalidia [21]

The part B of the question is missing and it is;

b) What is the height between the two window ledges?

Answer:

A) 20.76 m/s

B) 161.52 m

Explanation:

A) To calculate the initial speed we use the formula from Newton's first law of motion:

v = u + at

Making u the subject gives;

u = v - at

Where;

v is the final velocity which is the speed when Jill sees the pot = 60 m/s

u is the initial velocity which is the speed when Jack sees the pot go by

t is the time between the two observed events = 4 s

a in this question is acceleration due to gravity = 9.81 m/s².

Plugging in the relevant values into the initial velocity equation gives;

u = 60 - (9.81 × 4)

u = 20.76 m/s

B) To get the height difference, we will use the formula;

(y1 - y0) = ut + ½at²

Thus, plugging in the relevant values, we have;

y1 - y0 = (20.76 × 4) + (½ × 9.81 × 4²)

(y1 - y0) = 161.52 m

3 0

4 years ago

A ray of light traveling in air is incident on the surface of a block of clear ice (of index 1.309) at an angle of 25.5 ◦ with t

sergij07 [2.7K]

Answer: $135.29\º$

The figure attached will be helpful to understand the solution.

Here we see two cases, reflection and refraction of light.

According to the laws of reflection:

1. The incident ray, the reflected ray and the normal are in the same plane.

2. The angle of incidence is equal to the angle of reflection.

<u>*Note the normal is perpendicular to the plane, with a $90\º$ angle with the surface</u>

And this can be visualized in the figure, where the angle ${\theta}_{1}$ with which the incident ray hits the surface is equal to the angle with which this same ray is reflected.

On the other hand we have Refraction, a phenomenon in which the light bends or changes its direction when passing through a medium with a refractive index different from the other medium.

In this context, the Refractive index is a number that describes how fast light propagates through a medium or material.

According to Snell’s Law:

$n_{1}sin(\theta_{1})=n_{2}sin(\theta_{2})$ (1)

Where:

$n_{1}=1$ is the first medium refractive index (the air)

$n_{2}=1.309$ is the second medium refractive index (the ice)

$\theta_{1}=25.5\º$ is the angle of the incident ray

$\theta_{2}$ is the angle of the refracted ray

Now, firstly we have to find $\theta_{2}$ and then, by geometry, find $\alpha$ and $\beta$ which sum the <u>angle between the reflected and the refracted light</u>.

Finding $\theta_{2}$ from (1):

$(1)sin(25.5\º)=(1.309)sin(\theta_{2})$

$sin(\theta_{2})=0.328$

$\theta_{2}=arcsin(0.328)$

$\theta_{2}=19.201\º$ (2)

Remembering that the Normal makes a $90\º$ angle with the surface, we can say:

$90\º=\theta_{1}+\beta$ (3)

Finding $\beta$ :

$\beta=90\º-25.5\º=64.5\º$ (4)

Doing the same with $\theta_{2}$ and $\alpha}$ :

$90\º=\theta_{2}+\alpha$ (5)

Finding $\alpha$ :

$\alpha=90\º-19.201\º=70.79\º$ (6)

Adding both angles (4) and (6):

$\alpha+\beta=70.79\º+64.5\º$ (7)

$\alpha+\beta=135.29\º$ >>>This is the angle between the reflected and the refracted light.

5 0

3 years ago

Physics student is dropped. If they reach the floor at a speed of 3.2 m/s, from what height did they fall?

Mekhanik [1.2K]

Answer:

0.52 m

Explanation:

The motion of the studnet is an accelerated motion, with constant acceleration $g=9.8 m/s^2$ (acceleration of gravity) toward the ground. We can find the distance covered by the student (which is equal to the height from which he falls) by using the SUVAT equation:

$v^2 -u^2 = 2ad$

where

v = 3.2 m/s is the final speed

u = 0 is the initial speed

a = 9.8 m/s^2 is the acceleration

d is the distance covered

By re-arranging the equation, we find:

$d=\frac{v^2-u^2}{2a}=\frac{(3.2 m/s)^2-0}{2(9.8 m/s^2)}=0.52 m$

5 0

4 years ago

Suppose that we replace the aluminum with a mystery metal and repeat the experiment in the video. As in the video, the mass of t

dimaraw [331]

Answer:

b) one-third as great.

Explanation:

As we know that same heat is supplied in this experiment

so we will have

$Q = ms\Delta T$

now we know that both are initially at same temperature

then their final temperatures are

$T_1 = 40 degree$

$T_2 = 80 degree$

now we have

$m_1s_1 (40 - 20) = m_2s_2(80 - 20)$

so we have

$m_2s_2 = \frac{20}{60} m_1s_1$

so heat capacity of mystery metal is 1/3 times that of water

6 0

3 years ago

Read 2 more answers

Explain why a person who has runny nose is unable to detect smells clearly.

Orlov [11]

If you have a runny nose then the mucus will block the path that smell goes through. So if you are trying to smell a flower then you will have a hard time because the mucus is in the way, or blocking the entrance path. Hope this helps:)

May I please have brainliest?

3 0

3 years ago

Read 2 more answers