The graph shows you three different projections of human population growth

?a wire is stretched 30% what is the percentage change in resistance

Marat540 [252]

Answer:

The percentage change in resistance of the wire is 69%.

Explanation:

Resistance of a wire can be determined by,

R = (ρl) ÷ A

Where R is its resistance, l is the length of the wire, A its cross sectional area and ρ its resistivity.

When the wire is stretched, its length and area changes but its volume and resistivity remains constant.

$l_{o}$ = 1.3l, and $A_{o}$ = $\frac{A}{1.3}$

So that;

$R_{o}$ = (ρ $l_{o}$ ) ÷ $A_{o}$ = (ρ × 1.3l) ÷ ( $\frac{A}{1.3}$ )

= (1.3lρ) ÷ ( $\frac{A}{1.3}$ )

= $(1.3)^{2}$ × [(ρl) ÷ A]

= 1.69R (∵ R = (ρl) ÷ A)

$R_{o}$ = 1.69R

Where $R_{o}$ is the new resistance, $l_{o}$ is the new length, and $A_{o}$ is the new area after stretching the wire.

The change in resistance of the wire = $R_{o}$ - R

= 1.69R - 1R

= 0.69R

The percentage change in resistance = $\frac{0.69R}{R}$ × 100

= 0.69 × 100

= 69%

The percentage change in resistance of the wire is 69%.

3 0

3 years ago

What kinds of bonds can happen between the elements of a compound

Anit [1.1K]

What kinds of bonds can happen between the elements of a compound?

<span>Covalent and Ionic</span>

4 0

3 years ago

How long must a simple pendulum be if it is to make exactly six swings per second? (that is, one complete vibration takes exactl

MA_775_DIABLO [31]

The period of a simple pendulum is given by:
$T=2 \pi \sqrt{ \frac{L}{g} }$
where L is the length of the pendulum and g is the gravitational acceleration.

The pendulum in our problem makes one complete vibration in 0.333 s, so its period is T=0.333 s. Using this information, we can re-arrange the previous formula to find the length of the pendulum, L:
$L= g \frac{T^2}{(2 \pi)^2}=(9.81 m/s^2) \frac{(0.333 s)^2}{(2 \pi)^2}=0.028 m$

6 0

3 years ago

Care din propozitiile de mai jos sunt propozitii simple si care sunt propozitii dezvoltate? Argumentati oral raspunsurile a) mâț

Nataliya [291]

Answer:

a) developed

b) simple

c) simple

d) developed

e) developed

f) developed

Question:

Which of the following sentences are simple sentences and which are developed sentences? Orally argue the answers

a) the cat scribbled the little girl.

b) Grandma will cook

c) The cat will spin

d) You don't love cats?

e) in one jump, the cat will be at the window

f) we will never arrived on time

Explanation:

To differentiate the simple sentences from the developed sentences, let's understand what they are.

A Simple sentence is a sentence that contain a subject and a predicate. The sentence is complete in thought.

A developed sentence is a sentence that contain a subject, predicate as well as other parts of sentence.

a) the cat scribbled the little girl (developed)

b) Grandma will cook (simple)

c) The cat will spin (simple)

d) You don't love cats? (developed)

e) in one jump, the cat will be at the window (developed)

f) we will never arrived on time (developed)

Hence option b and c are simple sentences, while options a, d, e and f are developed.

6 0

3 years ago

One car drives north at 60 mph. Another car leaces 30 minutes later and drives south at 50 mph. How long will it take for the tw

Softa [21]

After the second car starts out,

D = 30 + 110 H

360 = 30 + 110 H

330 = 110 H

H = 330/110

H = 3 hours after the second car leaves.

That's 3.5 hours after the first car leaves.

8 0

3 years ago