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3 years ago

A pendulum oscillates 12 times in 4 seconds. what is the length of the pendulum?

Physics

1 answer:

seraphim [82]3 years ago

6 0

Answer:

L = 2.8 cm

Explanation:

Period T = 4 / 12 = 1/3 s

T = 2π√(L/g)

L = (T/2π)²g

L = ((1/3)/2π)²9.8 = 0.02758... ≈ 2.8 cm

You might be interested in

A man of mass 85 kg runs up a flight of stairs of height 4.6 m in a time period

seraphim [82]

Explanation:

a) Power = work / time = force × distance / time

P = Fd/t

P = (85 kg × 9.8 m/s²) (4.6 m) / (12 s)

P ≈ 319 W

b) P = Fd/t

0.70 (319 W) = (m × 9.8 m/s²) (4.6 m) / (9.6 s)

m = 47.6 kg

7 0

3 years ago

A woman falls to the ground while wearing a parachute. The air resistance on the parachute of the parachute is 500N. If the woma

scoundrel [369]

The gravitational force on the woman is A) 500 N

Explanation:

There are two forces acting on the woman during her fall:

The force of gravity, $F_G$ , acting downward
The air resistance, $F_D$ , acting upward

According to Newton's second law, the net force acting on the woman is equal to the product between the woman's mass and her acceleration:

$\sum F=ma$

where m is the mass of the woman and a her acceleration.

The net force can be written as

$\sum F = F_G - F_D$

Also, we know that the woman falls at a constant velocity (5 m/s), this means that her acceleration is zero:

$a=0$

Combining the equations together, we get:

$F_G-F_D = 0$

which means that the magnitude of the gravitational force is equal to the magnitude of the air resistance:

$F_G=F_D=500 N$

Learn more about forces and Newton's second law:

brainly.com/question/3820012

#LearnwithBrainly

5 0

3 years ago

Read 2 more answers

Why do some objects fall faster than others?

monitta

Answer:

Weight and Mass !!!!!!

Explanation:

Galileo discovered that objects that are more dense, or have more mass, fall at a faster rate than less dense objects, due to this air resistance. A feather and brick dropped together. Air resistance causes the feather to fall more slowly.

3 0

3 years ago

A car starts from rest and accelerates uniformly at 2.0 m/s2 toward the north. A second car starts from rest 4.0 s later at the

yKpoI14uk [10]

Answer:

the correct solution is 13 s

Explanation:

This is a kinematic problem, let's use accelerated rectilinear motion relationships.

For the first car it has an accelerometer of 2.0 m/s²

x = v₀₁ t + ½ a₁ t²

The second car leaves the same point, but 4.0 seconds later

x = v₀₂ (t-4) + ½ a₂ (t-4)²

With this form we use the same time for both cars.

The initial speeds are zero for both vehicles leave the rest, at the point where they are located has the same position

x = ½ a₁ t²

x = ½ a₂ (t-4)²

Let's solve

a₁ t² = a₂ (t-4)²

a₁/a₂ t² = t² -2 4 t + 16

t² (1- 2.0 / 4.0) - 8 t +16

t² 0.5 - 8 t +16 = 0

t² -16 t + 32 = 0

Let's solve the second degree equation

t = [16 ±√( 16² - 4 32)] / 2

t = ½ (16 ± 11,3)

Solutions

t1 = 13.66 s

t2 = 2.34 s

These are the mathematical solutions for the meeting point, but car 2 leaves after 4 seconds, so the only solution is 13.66 s

the correct solution is 13 s, if you have to select one the nearest 12s

6 0

3 years ago

Why can’t a real machine ever have 100% efficiency

Harman [31]

Answer:

Almost all machines require energy to offset the effects of gravity, friction, and air/wind resistance. Thus, no machine can continually operate at 100 percent efficiency.

4 0

3 years ago