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3 years ago

True or false Before Newton discovered gravity people could fly

Physics

1 answer:

Sonja [21]3 years ago

8 0

False. Gravity was always here but no one really thought about it until Isaac Newton did.

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A laser beam of wavelength 600 nm is incident on two slits that are separated by 0.02 mm. What is the separation between adjacen

Liula [17]

Answer:

option D

Explanation:

given,

wavelength = 600 nm

width of separation = 0.02 mm

L = 5 m

for mth order maxima

$d \times \dfrac{y_m}{L}=m\lambda$

for (m+1)th order maxima

$d \times \dfrac{y_{m+1}}{L}=(m+1)\lambda$

now,

$y_m=\dfrac{mL\lambda}{d}$ and

$y_{m+1}=\dfrac{(m+1)L\lambda}{d}$

hence,

$\Delta y = y_{m+1} - y_m$

$\Delta y =\dfrac{L\lambda}{d}$

$\Delta y =\dfrac{5 \times 600 \times 10^{-9}}{0.02 \times 10^{-3}}$

$\Delta y =0.15\ m$

$\Delta y =15\ cm$

hence, the correct answer is option D

4 0

4 years ago

Josh has a toy car of mass 3 kg tied to a string of length 2 m. He ties the string to a pole and has the toy car drive in a circ

gulaghasi [49]

Part a)

Centripetal acceleration is defined as

$a_c = \frac{v^2}{R}$

now here we know that

$v = 3m/s$

$R = 2 m$

m = 3 kg

now from above formula we have

$a_c = \frac{3^2}{2}$

$a_c = 4.5 m/s^2$

Part b)

Maximum possible tension in the string is given as

$T = 50 N$

now by force equation we have

$F = ma$

$50 = 3 a$

$a = \frac{50}{3} m/s^2$

now again by above formula

$\frac{v^2}{R} = \frac{50}{3}$

$v = \sqrt{\frac{50 \times 2}{3}}$

$v = 5.77 m/s$

5 0

4 years ago

Read 2 more answers

The St. Louis Arch has a height of 192 m. Suppose that a stunt woman of mass 84 kg jumps off the top of the arch with an elastic

Hitman42 [59]

To solve this problem it is necessary to apply the kinematic equations of motion for speed and distance, as well as the concepts related to kinetic energy.

The change in the height of a body subject to gravity is given by

$h = \frac{1}{2} gt^2 \rightarrow t = \sqrt{\frac{2h}{g}}$

Where

h = Height

g =Gravity

t = time

Replacing with our values we have that the time is

$t = \sqrt{\frac{2h}{g}}$

$t = \sqrt{\frac{2(192)}{9.8}}$

$t = 6.25s$

From speed as a function of change between acceleration and time we have then that after 2.6 seconds the speed would be

$g = \frac{v}{t} \rightarrow v = g*t$

$v = 9.8*2.6$

$v = 25.48m/s$

The kinetic energy would be given by

$KE = \frac{1}{2} mv^2$

$KE = \frac{1}{2} (84)(25.48)$

$KE = 1070.16J$

Therefore the kinetic energy after 2.6s is 1070.16J

6 0

3 years ago

Abigail runs one complete lap (400m) around the track, while Gabi runs a 50 meter dash in a straight line. Which runner had a gr

Ipatiy [6.2K]

Answer:

$\boxed {\boxed {\sf Gabi \ had \ greater \ displacement}}$

Explanation:

Displacement is the change in the position of an object.

Abigail runs a complete lap around the track, which is 400 meters. Even though she ran 400 meters, she has no displacement. If she starts and ends at the same spot, there is no change in position.

Gabi runs a 50 meter dash in a straight line. Gabi has 50 meters of displacement. She runs in a straight line and is 50 meters away from where she began.

While Abigail ran the farther distance, Gabi had the greater displacement.

4 0

3 years ago

Read 2 more answers

There is no sound in the vaccuum of space. Why? Select all that apply

miss Akunina [59]

#1 and #3 are correct.

#3 is slightly goofy.
The problem is not that there's no air to vibrate your eardrum.
The problem with no air is that there's nothing to ever bring the sound
to your head, even if you're only a foot away from the source. There
are just NO SOUND WAVES going on at all.

7 0

3 years ago