Match the elements with its definition.

A sample contains 20 kg of radioactive material. The decay constant of the material is 0.179 per second. If the amount of time t

Nataly [62]

Answer:

Explanation:

Given

N0 = 20kg (original substance)

decay constant λ = 0.179/sec

time t = 300s

We are to find N(t)

Using the formula;

n(t) = N0e^-λt

Substitute the given values

N(t) = 20e^-(0.179)(300)

N(t) = 20e^(-53.7)

N(t) = 20(4.7885)

N(t) =143.055

To know how much of the original material that is active, we will find N(t)/N0 = 143.055/20 = 7.152

About 7 times the original material is still radioactive

4 0

3 years ago

A bicycle is traveling north at 5.0 m/s. The mass of the wheel, 2.0 kg, is uniformly distributed along the rim, which has a radi

andreev551 [17]

Answer:2

Explanation:

Given

Velocity of bicycle is 5 m/s towards north

radius of rim $r=20 cm$

mass of rim $m=2 kg$

Angular momentum $\vec{L}=I\cdot \vec{\omega }$

$I=mr^2=2\times 0.2^2=0.08 kg-m^2$

$\omega =\frac{v}{r}=\frac{5}{0.2}=25 rad/s$

$L=0.08\times 25=2kg-m^2/s$

direction of Angular momentum will be towards west

7 0

3 years ago

PLEASE help its timed..

mojhsa [17]

Answer:

D

Explanation:

by increasing the distance through which force is applied, by changing the direction of force applied or by multiplying force of speed of the energy applied

3 0

3 years ago

Can anyone help me on this thnxs

DIA [1.3K]

Answer:

a sin Ø - b cos Ø

_______________. =

a sin Ø+ b cos Ø

=> a - b cot ∅

_____________

a + b cot ∅

=> a - b x b

__

a

______________

a + b x b

___

a

=> a² - b ²

__________

a ² + b²

8 0

3 years ago

Find the equivalent resistance, the current supplied by the battery and the current through each resistor when the specified res

VLD [36.1K]

Answer:

$R_{eq}$ = 19 Ω, I = 0.105 A, V1 = 1.05 V and V2 = 0.95 V

Explanation:

The correct way to solve this type of problem is to find the current or voltage values for the equivalent resistance and from here find the other values.

For a series circuit the equivalent resistance is the sum of the resistance

$R_{eq}$ = R1 + R2

$R_{eq}$ = 10 +9

$R_{eq}$ = 19 Ω

Let's use the equation for the voltage

V = I $R_{eq}$

I = V / $R_{eq}$

I = 2/19

I = 0.105 A

In a series circuit the current is constant, so let's use the voltage equation for each resistor

V1 = I R1

V1 = 0.105 10

V1 = 1.05 V

V2 = 0.105 9

V2 = 0.95 V

Note that the sum of this voltage is the total voltage applied.

6 0

3 years ago