1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Alexandra [31]
2 years ago
9

When did galileo discover projectile motion?

Physics
1 answer:
Tcecarenko [31]2 years ago
4 0
Between 1589-1592 when he discovered projecctile motion
You might be interested in
2. In your own words, what is direct plagiarism?
alekssr [168]

Answer:

copying another writer's work with no attempt to acknowledge that the material was found in external source is considered as a direct plagiarism.

7 0
2 years ago
Read 2 more answers
What is the evidence proving that we're in the 6th mass extinction?
Sveta_85 [38]

Answer:

Global warming and climate change

8 0
2 years ago
Two satellites are in circular orbits around the earth. The orbit for satellite A is at a height of 403 km above the earth’s sur
BARSIC [14]

Answer:

v_A=7667m/s\\\\v_B=7487m/s

Explanation:

The gravitational force exerted on the satellites is given by the Newton's Law of Universal Gravitation:

F_g=\frac{GMm}{R^{2} }

Where M is the mass of the earth, m is the mass of a satellite, R the radius of its orbit and G is the gravitational constant.

Also, we know that the centripetal force of an object describing a circular motion is given by:

F_c=m\frac{v^{2}}{R}

Where m is the mass of the object, v is its speed and R is its distance to the center of the circle.

Then, since the gravitational force is the centripetal force in this case, we can equalize the two expressions and solve for v:

\frac{GMm}{R^2}=m\frac{v^2}{R}\\ \\\implies v=\sqrt{\frac{GM}{R}}

Finally, we plug in the values for G (6.67*10^-11Nm^2/kg^2), M (5.97*10^24kg) and R for each satellite. Take in account that R is the radius of the orbit, not the distance to the planet's surface. So R_A=6774km=6.774*10^6m and R_B=7103km=7.103*10^6m (Since R_{earth}=6371km). Then, we get:

v_A=\sqrt{\frac{(6.67*10^{-11}Nm^2/kg^2)(5.97*10^{24}kg)}{6.774*10^6m} }=7667m/s\\\\v_B=\sqrt{\frac{(6.67*10^{-11}Nm^2/kg^2)(5.97*10^{24}kg)}{7.103*10^6m} }=7487m/s

In words, the orbital speed for satellite A is 7667m/s (a) and for satellite B is 7487m/s (b).

7 0
2 years ago
A girl is sledding down a slope that is inclined at 30º with respect to the horizontal. The wind is aiding the motion by providi
OleMash [197]

Answer:

The sled required 9.96 s to travel down the slope.

Explanation:

Please, see the figure for a description of the problem. In red are the x and y-components of the gravity force (Fg). Since the y-component of Fg (Fgy) is of equal magnitude as Fn but in the opposite direction, both forces get canceled.

Then, the forces that cause the acceleration of the sled are the force of the wind (Fw), the friction force (Ff) and the x-component of the gravity force (Fgx).

The sum of all these forces make the sled move. Finding the resulting force will allow us to find the acceleration of the sled and, with it, we can find the time the sled travel.

The magnitude of the friction force is calculated as follows:

Ff = μ · Fn

where :

μ = coefficient of kinetic friction

Fn =  normal force

The normal force has the same magnitude as the y-component of the gravity force:

Fgy = Fg · cos 30º = m · g · cos 30º

Where

m = mass

g = acceleration due to gravity

Then:

Fgy = m · g · cos 30º = 87.7 kg · 9.8 m/s² · cos 30º

Fgy = 744 N

Then, the magnitude of Fn is also 744 N and the friction force will be:

Ff = μ · Fn = 0.151 · 744 N = 112 N

The x-component of Fg, Fgx, is calculated as follows:

Fgx = Fg · sin 30º = m·g · sin 30º = 87.7 kg · 9.8 m/s² · sin 30º = 430 N

The resulting force, Fr, will be the sum of all these forces:

Fw + Fgx - Ff = Fr

(Notice that forces are vectors and the direction of the friction force is opposite to the other forces, then, it has to be of opposite sign).

Fr = 161 N + 430 N - 112 N = 479 N

With this resulting force, we can calculate the acceleration of the sled:

F = m·a

where:

F = force

m = mass of the object

a = acceleration

Then:

F/m = a

a = 479N/87.7 kg = 5.46 m/s²

The equation for the position of an accelerated object moving in a straight line is as follows:

x = x0 + v0 · t + 1/2 · a · t²

where:

x = position at time t

x0 = initial position

v0 = initial velocity

t = time

a = acceleration

Since the sled starts from rest and the origin of the reference system is located where the sled starts sliding, x0 and v0 = 0.

x = 1/2· a ·t²

Let´s find the time at which the position of the sled is 271 m:

271 m = 1/2 · 5.46 m/s² · t²

2 · 271 m / 5.46 m/s² = t²

<u>t = 9.96 s </u>

The sled required almost 10 s to travel down the slope.

8 0
3 years ago
The part of a vompressional wave that has the lowest density is the
Yuri [45]
Longitudinal waves have energy that vibrates parallel to the medium - a compression is the region of greatest density and the rarefaction the region of highest density .The rarefaction (much like the maximum amplitude in a transverse wave) has a region of lowest density, typically situated in the exact center of the region.
8 0
3 years ago
Other questions:
  • The 16.0-in. spring is compressed to a 9.9-in. length, where it is released from rest and accelerates the sliding block A. The a
    12·1 answer
  • Which of the following statements is correct regarding transformers?
    12·2 answers
  • You add 500 mL of water at 10°C to 100 mL of water at 70°C. What is the
    10·1 answer
  • What is the condition to earths atmosphere at a givin time and pace
    6·1 answer
  • A bungee cord with a spring constant of 800 stretches 6 meters at its greatest displacement. How much elastic potential energy d
    9·1 answer
  • Alkaline batteries have the advantage of putting out constant voltage until very nearly the end of their life. How long will an
    8·1 answer
  • Why does the density of a substance remain the same for different amounts of the substance
    11·1 answer
  • Two speakers in a stereo emit identical pure tones. As you move around in front of the speakers, you hear the sound alternating
    11·1 answer
  • Turning up the Heat
    12·1 answer
  • Based on the tug of war pictured below, what is the net force? –190 N 10 N –10 N 190 N.
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!