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
melomori [17]
3 years ago
10

A student who weighs 550 N is wearing a backpack that weighs 80 N. The student is standing still on level ground. Give your answ

ers to the following questions in newtons. Remember, enter only the number; don't try to enter the units.a) What is the magnitude of the net force on the student?
b) What is the magnitude of the contact force on the student by the backpack?
c) What is the magnitude of the contact force on the student by the ground?
Physics
1 answer:
siniylev [52]3 years ago
6 0

Answer:

Explanation:

a) The magnitude of the net force on the student = 0 N since the student is standing still on level ground and upward reaction force = downward force.

b) the magnitude of the contact force on the student by the backpack = 80 N since the student was backing the backpack

c) the magnitude of the contact force o the student by the ground = 550 N + 80 N = 630 N reactional force on the student

You might be interested in
Two small spheres with mass 10 gm and charge q, are suspended from a point by threads of length L=0.22m. What is the charge on e
Nataliya [291]

Answer:

q=1.95*10^{-7}C

Explanation:

According to the free-body diagram of the system, we have:

\sum F_y: Tcos(15^\circ)-mg=0(1)\\\sum F_x: Tsin(15^\circ)-F_e=0(2)

So, we can solve for T from (1):

T=\frac{mg}{cos(15^\circ)}(3)

Replacing (3) in (2):

(\frac{mg}{cos(15^\circ)})sin(15^\circ)=F_e

The electric force (F_e) is given by the Coulomb's law. Recall that the charge q is the same in both spheres:

(\frac{mg}{cos(15^\circ)})sin(15^\circ)=\frac{kq^2}{r^2}(4)

According to pythagoras theorem, the distance of separation (r) of the spheres are given by:

sin(15^\circ)=\frac{\frac{r}{2}}{L}\\r=2Lsin(15^\circ)(5)

Finally, we replace (5) in (4) and solving for q:

mgtan(15^\circ)=\frac{kq^2}{(2Lsin(15^\circ))^2}\\q=\sqrt{\frac{mgtan(15^\circ)(2Lsin(15^\circ))^2}{k}}\\q=\sqrt{\frac{10*10^{-3}kg(9.8\frac{m}{s^2})tan(15^\circ)(2(0.22m)sin(15^\circ))^2}{8.98*10^{9}\frac{N\cdot m^2}{C^2}}}\\q=1.95*10^{-7}C

5 0
3 years ago
demonstrate in a brief paragraph how the search to explain planetary orbits exemplifies the scientific method and then use of mo
kari74 [83]

Answer:

People firstly believe that the planets move in a circular orbit until Newton came up with his hypothesis by inventing calculus so that we could understood and calculated planetary orbits and their accuracy.

Explanation:

  • Everyone assumed the planets were perfect circles until Newton came up with an idea. Slowly people would make maps of the orbits that added circles on circles, and they could never really explain about the movement of the planet. They simply say that planets move on circles but they lacked the math to explain or prove it. Then Newton came up with an idea of inventing calculus so that we could understood and calculated planetary orbits and their accuracy.
  • Firstly people used their observations and say that the orbits looked like circles, then they developed their models and did the math, and proposed their hypothesizes which were wrong, until Newton came along and tried to match a model that used elliptical orbits and invented the math that allowed him to make predictions with it. His model worked for most planets.
  • However he could not explain about the planet Mercury for instance since it was a very strange orbit. Then after the Einstein's theory of General Relativity he could also explain very deeply about it.
  • Scientists and Astronomers made hypothesizes that there was another planet orbiting too close to the sun to see with telescopes, called Vulcan, that explained mercury's orbit before Einstein's theory. Then long after we had telescopes which was good enough to see if there was a planet orbiting closer to the sun than mercury.  
8 0
2 years ago
Two identical resistors are connected in parallel across a 26-V battery, which supplies them with a total power of 7.1 W. While
Gnom [1K]

Answer:

A) R = 190.42 Ω

B) P = 5.325 W

Explanation:

We are given;

Total power;P_tot = 7.1 W

Voltage;V = 26 V

A)We are told that while the battery is still connected, one of the resistors is heated, so that its resistance doubles.

Thus, the power is doubled.

Now, formula for power is;

P = IV

Thus, since power is doubled, we have;

P = 2(IV)

Now, formula for current is; I = V/R

So, P = 2V²/R

Making R the subject, we have;

R = 2V²/P

In this question, P is p_total = 7.1 W

Thus;

R = (2 × 26²)/7.1

R = 190.42 Ω

B) Now, the resistance of the resistors are R and 2R.

Formula for power in this context is;

P = V²/R

Thus,

Total power delivered to the resistors is;

P = V²/R + V²/2R

P = 3V²/2R

P = (3 × 26²)/(2 × 190.42)

P = 5.325 W

8 0
3 years ago
Plate Tectonic Theory
Vitek1552 [10]

Answer:

its d

Explanation:

6 0
3 years ago
a uniform rule balance on a knife edge at the 55cm mark when a mass of 40g is hung from the 95cm mark. find the weight of the ru
BigorU [14]

Answer:

W = 3.1 N

Explanation:

moments about any convenient point will sum to zero.

I choose summing about the knife edge mark and will assume the ruler of weight W is of uniform construction.

I will assume the ruler weight makes a positive moment

W[55 - 50) - 0.040(9.8)[ 95 - 55] = 0

                                                5W = 15.68

                                                   W = 3.136

7 0
2 years ago
Other questions:
  • Which of the following body systems work together to get sells the oxygen they need to carry at the cellular respiration
    12·1 answer
  • Red, green, and blue light rays each enter a drop of water from the same direction.Which light ray's path through the drop will
    11·1 answer
  • Explain briefly work energy and power
    11·1 answer
  • A 750 kg car is moving at 20.0 m/s at a height of 5.0 m above the bottom of a hill when it runs out of gas. From there, the car
    11·1 answer
  • Write down the role played by four digestive juices in digestion and the
    10·1 answer
  • Acceleration is defined as the rate of change of position true or false
    7·2 answers
  • Find out how the position of the Sun would be different at 12:00 midday in December than in June. What path would the sun take f
    10·1 answer
  • A block of mass 8 m can move without friction
    8·1 answer
  • A circuit is constructed with six resistors and two batteries as shown. The battery voltages are V1 = 18 V and V2 = 12 V. The po
    10·1 answer
  • two charges are placed at corners A and B of a square of side length. How much work is needed to move a charge from point C to D
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!