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
Sphinxa [80]
3 years ago
10

I meed help with these 2 questions plz

Physics
1 answer:
ludmilkaskok [199]3 years ago
4 0

-- 30N

-- the sum of all the forces

You might be interested in
A 525 kg satellite is in a circular orbit at an altitude of 575 km above the Earth's surface. Because of air friction, the satel
Dafna1 [17]

Answer:

1.69\cdot 10^{10}J

Explanation:

The total energy of the satellite when it is still in orbit is given by the formula

E=-G\frac{mM}{2r}

where

G is the gravitational constant

m = 525 kg is the mass of the satellite

M=5.98\cdot 10^{24}kg is the Earth's mass

r is the distance of the satellite from the Earth's center, so it is the sum of the Earth's radius and the altitude of the satellite:

r=R+h=6370 km +575 km=6945 km=6.95\cdot 10^6 m

So the initial total energy is

E_i=-(6.67\cdot 10^{-11})\frac{(525 kg)(5.98\cdot 10^{24} kg)}{2(6.95\cdot 10^6 m)}=-1.51\cdot 10^{10}J

When the satellite hits the ground, it is now on Earth's surface, so

r=R=6370 km=6.37\cdot 10^6 m

so its gravitational potential energy is

U = -G\frac{mM}{r}=-(6.67\cdot 10^{-11})\frac{(525 kg)(5.98\cdot 10^{24}kg)}{6.37\cdot 10^6 m}=-3.29\cdot 10^{10} J

And since it hits the ground with speed

v=1.90 km/s = 1900 m/s

it also has kinetic energy:

K=\frac{1}{2}mv^2=\frac{1}{2}(525 kg)(1900 m/s)^2=9.48\cdot 10^8 J

So the total energy when the satellite hits the ground is

E_f = U+K=-3.29\cdot 10^{10}J+9.48\cdot 10^8 J=-3.20\cdot 10^{10} J

So the energy transformed into internal energy due to air friction is the difference between the total initial energy and the total final energy of the satellite:

\Delta E=E_i-E_f=-1.51\cdot 10^{10} J-(-3.20\cdot 10^{10} J)=1.69\cdot 10^{10}J

8 0
3 years ago
A sphere has a radius of 3.9cm and a density of 7.58 g/cm cubed. What is the mass?
snow_lady [41]

Answer:

m=ρV

V=4/3 * pi * r3

V=1.3 * 3.14 * 3.9^3

V=242.14 cm^3

m=7.58 * 242.14

m=1.8 kG

Explanation:

1. We calculate volume for sphere.

2. Then we calculate mass of sphere.

3 0
3 years ago
Which object has the greatest inertia? *
____ [38]
One with greater mass (8kg)
4 0
3 years ago
Read 2 more answers
A sealed tank containing seawater to a height of 12.8 m also contains air above the water at a gauge pressure of 2.90 atm . Wate
exis [7]

Answer:

The velocity of water at the bottom, v_{b} = 28.63 m/s

Given:

Height of water in the tank, h = 12.8 m

Gauge pressure of water, P_{gauge} = 2.90 atm

Solution:

Now,

Atmospheric pressue, P_{atm} = 1 atm = 1.01\tiems 10^{5} Pa

At the top, the absolute pressure, P_{t} = P_{gauge} + P_{atm} = 2.90 + 1 = 3.90 atm = 3.94\times 10^{5} Pa

Now, the pressure at the bottom will be equal to the atmopheric pressure, P_{b} = 1 atm = 1.01\times 10^{5} Pa

The velocity at the top, v_{top} = 0 m/s, l;et the bottom velocity, be v_{b}.

Now, by Bernoulli's eqn:

P_{t} + \frac{1}{2}\rho v_{t}^{2} + \rho g h_{t} = P_{b} + \frac{1}{2}\rho v_{b}^{2} + \rho g h_{b}

where

h_{t} -  h_{b} = 12.8 m

Density of sea water, \rho = 1030 kg/m^{3}

\sqrt{\frac{2(P_{t} - P_{b} + \rho g(h_{t} - h_{b}))}{\rho}} =  v_{b}

\sqrt{\frac{2(3.94\times 10^{5} - 1.01\times 10^{5} + 1030\times 9.8\times 12.8}{1030}} =  v_{b}

v_{b} = 28.63 m/s

5 0
3 years ago
The equation below is used to calculate the mechanical advantage of an ideal wheel and axle.
Jet001 [13]

Answer:

b

Explanation:

6 0
3 years ago
Other questions:
  • An airplane flies in a horizontal circle of radius 500 m at a speed of 150 m/s. If the radius were changed to 1000 m, but the sp
    15·1 answer
  • Which of the following is the FINAL step in a forecasting​ system?A.Validate and implement the results.B.Select the forecast​ mo
    12·1 answer
  • An object's potential energy is set it cannot change is this true
    12·2 answers
  • An electron in a(n) __________ subshell experiences the greatest effective nuclear charge in a many-electron atom.
    11·1 answer
  • in order to generate electricity, nuclear powerplants take advantage of this part of the electromagnetic spectrum
    10·1 answer
  • A boy throws rocks with an initial velocity of 12m/s [down] from a 20 m bridge into a river. Consider the river to be at a heigh
    5·1 answer
  • Question /
    5·1 answer
  • A 6.50 meter high cylinder is filled with alcohol(density =806 kg/m^3). What is the pressure at the bottom of the cylinder?
    13·1 answer
  • 3. Which of the following statements is not true about Gauss’s law?
    13·2 answers
  • A turtle accelerates from a stop at 3m/s/s to the South for 8s. What is the turtle’s final velocity? Show your work and include
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!