1. Oil or water clinging to a surface of a jar is an example of:

A scooter has a mass of 250. Kg. A constant force is exerted on it for 60.0 S. during the time the force is exerted, the scooter

kodGreya [7K]

Answer:

Explanation:

change in momentum = m ( v - u ) ; m is mass , V is final velocity and u is initial velocity .

= 250 ( 28 - 6 )

= 5500. N.s

for calculating magnitude of force we shall apply the concept of impulse

Impulse = F X t = m( v-u ) ; F is force applied for time t .

F x 60 = 5500

F = 91.67 N .

force exerted = 91.67 N .

8 0

3 years ago

Circumference of a circle given the radius or diameter? explain why or why not

djyliett [7]

Circumference of a circle can be calculated if the radius or the diameter is given.

<u>Explanation</u>:

Circumference or the perimeter of a circle can be calculated if the radius or the diameter of the circle is given.
This is calculated by the formula - 2 * pi * r (if radius is given) and pi * d (if diameter is given) where pi = 3.14, r = radius and d = diameter
This calculation is based on the fact that the circumference is three and a little more times that of the radius. Since the diameter is double that of the radius, when the diameter is given formula becomes pi*d.

3 0

3 years ago

The chart below shows the amount of coal mined in four different states of USA in the year 2005.

ozzi

The correct answer is <span>Montana.

In fact, we see from the table that Montana is the state with the largest amount of coal mined in 2005: 120 billion tons, while all the other states have a smaller amount of coal mined (37, 68 and 78, for West Virginia, Wyoming and Illinois, respectively).</span>

3 0

4 years ago

Read 2 more answers

A spring of negligible mass stretches 3.00 cm from its relaxed length when a force of 7.50 N is applied. A 0.500-kg particle res

zhannawk [14.2K]

Answer:

a) 250 N/m

b) 22.4 rad/s , 3.6 Hz , 0.28 sec

c) 0.3125 J

Explanation:

a)

F = force applied on the spring = 7.50 N

x = stretch of the spring from relaxed length when force "F" is applied = 3 cm = 0.03 m

k = spring constant of the spring

Since the force applied causes the spring to stretch

F = k x

7.50 = k (0.03)

k = 250 N/m

b)

m = mass of the particle attached to the spring = 0.500 kg

Angular frequency of motion is given as

$w = \sqrt{\frac{k}{m}}$

$w = \sqrt{\frac{250}{0.5}}$

$w$ = 22.4 rad/s

$f$ = frequency

Angular frequency is also given as

$w$ = 2 π $f$

22.4 = 2 (3.14) f

$f$ = 3.6 Hz

$T$ = Time period

Time period is given as

$T = \frac{1}{f}$

$T = \frac{1}{3.6}$

$T$ = 0.28 sec

c)

A = amplitude of motion = 5 cm = 0.05 m

Total energy of the spring-block system is given as

U = (0.5) k A²

U = (0.5) (250) (0.05)²

U = 0.3125 J

5 0

4 years ago

Water drops from the nozzle of a shower onto the floor 81 inches below. The drops fall at regular intervals of time, the first d

Alexxx [7]

Answer:

0.91437 m

0.22859 m

Explanation:

g = Acceleration due to gravity = 9.81 m/s² = a

$s=81\ inches=81\times 0.0254=2.0574\ m$

$s=ut+\frac{1}{2}at^2\\\Rightarrow 2.0574=0t+\frac{1}{2}\times 9.81\times t^2\\\Rightarrow t=\sqrt{\frac{2.0574\times 2}{9.81}}\\\Rightarrow t=0.64764\ s$

When the time intervals are equal, if four drops are falling then we have 3 time intervals.

So, the time interval is

$t'=\dfrac{t}{3}\\\Rightarrow t'=\dfrac{0.64764}{3}\\\Rightarrow t'=0.21588\ s$

For second drop time is given by

$t''=2t'\\\Rightarrow t''=2\times 0.21588\\\Rightarrow t''=0.43176\ s$

Distance from second drop

$s=ut+\dfrac{1}{2}at^2\\\Rightarrow y''=ut''+\dfrac{1}{2}at''^2\\\Rightarrow s=0\times t+\dfrac{1}{2}\times 9.81\times 0.43176^2\\\Rightarrow s=0.91437\ m$

Distance from second drop is 0.91437 m

Distance from third drop

$s=ut+\dfrac{1}{2}at^2\\\Rightarrow y''=ut'+\dfrac{1}{2}at'^2\\\Rightarrow s=0\times t+\dfrac{1}{2}\times 9.81\times 0.21588^2\\\Rightarrow s=0.22859\ m$

Distance from third drop is 0.22859 m

6 0

3 years ago