What is the atomic number of potassium?

if jack was traveling north 120 miles and it took him 3 hours to get there. what is the velocity that jack was traveling? is thi

uysha [10]

Velocity of an object is given as

$velocity = \frac{displacement}{time}$

now we have

$displacement = 120 miles$

time = 3 hours

now from above formula

$v = \frac{120}{3}$

$v = 40 miles/hour$

so its velocity is 40 mph and its a vector quantity whose direction is towards NORTH

correct answer is B

7 0

4 years ago

Zain is standing on a bridge. He tosses a ball upwards, which rises, stops, and then falls all the way to the water (30 meters b

IgorC [24]

Answer:

A. 2.41 s.

B. 24.3 m/s.

Explanation:

vf = vi + 2a*t

where, vf = final velocity

= 0 m/s

vi = final velocity

= 1.5 m/s

a = 9.8 m/s^2

A.

ti = 1.5/(9.8 * 2)

= 0.08 s

Vf^2 = Vi^2 + 2a*s

1.5^2 = 2 * 9.8 * s

S = 0.115 m

Time taken to drop into the water,

30.115 = 1.5*to + 4.9*to^2

to = 2.33 s

Total time taken = ti + to

= 2.33 + 0.08

= 2.41 s.

B.

Vo = 0 m/s

S = 30.115 m

Vf = ?

Using,

Vf^2 = Vo^2 + 2*a*s

= sqrt (2*9.8*30.115)

= 24.3 m/s.

7 0

4 years ago

A student is doing an investigation into the masses of different materials of different densities.

Dmitrij [34]

Answer:

0.0118125 (kg)

Explanation:

mass = density x volume

First, find the volume of the cube as you're already given the density. You're also given the length of the cube, 1.5 cm. You need to convert this to m since the density's unit is kg/m^2

1.5cm x (1m/100cm) = 0.015m

Since Volume = (length)^3,

Volume of the cube = (0.015)^3

Volume of the cube = 3.375*10^-6

So mass of the cube = (3500)(3.375*10^-6) = 0.0118125 (kg)

5 0

3 years ago

What type of image is formed by a lens if m = -1.6?

anastassius [24]

The image formed from the lens is real, inverted and enlarged

Explanation:

The magnification of a lens is given by:

$m=\frac{y'}{y}=-\frac{q}{p}$ (1)

where:

y' is the size of the image

y is the size of the object

q is the distance of the image from the lens

p is the distance of the object from the lens

For this lens, the magnification is

m = -1.6

We notice the following:

- The magnification is negative

- The magnification is larger than 1

Looking at eq.(1), we can therefore make the following conclusions:

- SInce $m=\frac{y'}{y}$ and $|m|>1$ , it follows that $|y'|>|y|$ , so the image is larger than the object

- Since $m=\frac{y'}{y}$ and $m$ , it follows that $y'$ (since y > 0 for convention): this means that the image is inverted

- Since $m=-\frac{q}{p}$ and $m$ , it follows that $q>0$ (since p > 0 for convention): this means that the image is real

Learn more about lenses and mirrors here:

brainly.com/question/8737441

#LearnwithBrainly

5 0

3 years ago

Read 2 more answers

A 500N person stands 2.5m from a wall against which a horizontal beam is attached. The beam is 6m long and weighs 200N. A cable

Vinil7 [7]

PART A)

Here by force balance along Y direction

$Tsin45 + F_y = 500 + 200$

Force balance along X direction

$Tcos45 = F_x$

now by torque balance

$Tsin45 (6) = 500 (2.5) + 200 (3)$

$T(4.24) = 1250 + 600$

$T = 436.3 N$

PART B)

now from above equations

$Tsin45 + F_y = 700$

$F_y = 391.5 N$

$F_x = Tcos45 = 308.5 N$

now net reaction force of wall is given as

$F = \sqrt{F_x^2 + F_y^2}$

$F = 498.4 N$

5 0

3 years ago