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
Igoryamba
2 years ago
15

What causes a compass needle to point to geographic north?

Physics
1 answer:
morpeh [17]2 years ago
8 0
I believe it’s “C”
Hope that’s help you(:
You might be interested in
A person walks at a speed of 6 km/h from point A to point B. If he improves his pace by 1.5 km/h, he will arrive 1 hour earlier.
Fofino [41]

Answer:

a) The distance is 30 km

The time duration is 5 hours

b) s₁ is approximately 28.142 km or s₁ is approximately 1.505 km

Explanation:

The initial speed with of the person, v₁ = 6 km/h

The distance the walked by the person, d = From point A to point B

The rate at which the person increases the speed, Δv = 1.5 km/h

The time it takes for the person to arrive at point B from point A at the new speed, t₂ = 1 hour earlier than when walking at 6 km/h

a) Let t₁ represent the time it takes the person walking from point A to point B at 6 km/h, we have;

t₂ = t₁ - 1...(1)

d/t₁ = 6...(2)

d/t₂ = 6 + 1.5 = 7.5

∴ d/t₂ = 7.5...(3)

From equation (2), we have;

d = 6 × t₁ = 6·t₁

Plugging in d = 6·t₁, and t₂ = t₁ - 1 in equation (3) gives;

d/t₂ = 7.5

∴ 6·t₁/t₁ - 1 = 7.5

6·t₁ = 7.5 × (t₁ - 1) = 7.5·t₁ - 7.5

7.5·t₁ - 6·t₁ = 7.5

1.5·t₁ = 7.5

t₁ = 7.5/1.5 = 5

t₁  = 5

The time it takes the person walking from point A to point B at 6 km/h, t₁  = 5 hours

The distance from point A to point B, d = 6 km/h × 5 hours = 30 km

b) The distance the person travels at the initial speed, v₁ (6 km/h) = s₁

The duration the person pauses for a rest = 15 minutes = 1/4 hours

The speed with which he walks the rest of the journey, v₂ = 7.5 km/h

The time earlier than expected that he arrives, Δt = 30 minutes = 0.5 hours

We note that the total distance, d = 30 km

The expected time, t₁ = 5 hours

Therefore, we have;

s₁ + s₂ = 30 km

s₂ = 30 - s₁

v₁/s₁ + 1/4 + v₂/s₂ = t₁ - 0.5

Therefore;

6/s₁ + 1/4 + 7.5/(30 - s₁) = 5 - 0.5 = 4.5

6/28.142+ 1/4 + 7.5/(30 - 28.142) = 5 - 0.5 = 4.5

6/s₁ + 7.5/(30 - s₁) = 4.5 - 1/4 = 4.25

-(3·s₁ + 360)/(2·s₁²- 60·s₁) = 4.25

2·s₁²- 60·s₁) × 4.25 + 3·s₁ + 360 = 0

17·s₁²- 504·s₁ + 720 = 0

s₁ = (504 ± √((-504)² - 4 × 17 × 720))/(2 × 17)

s₁ ≈ 28.142 or s₁ = 1.505

The distance the individual travels at v₁ = 6 km/h, s₁ ≈ 28.142 km or 1.505 km

4 0
3 years ago
How did Albert Einstein come up with 3 = mc square pls help
inysia [295]

Answer: He came up with this by using theories like  the photoelectric effect, the second offered experimental proof of the existence of atoms, and the third introduced the theory of special relativity.

Explanation: He was explaing the realationship between energy and mass.

Me: Hope this helps!!! May I have brainlist!?

4 0
2 years ago
A constant magnetic flux through a closed loop of wire induces an emf in that loop. True or false?
miskamm [114]

Answer: False

Explanation: In order to explain this problem we have to use the Faraday law, which say

dФm/dt=-ε  it means that the variation of the magnetic field flux with time is equal to the emf ( electromotive force). In our case the magnetic flux is constant then there is not a emf induced in a wire closed loop.

6 0
3 years ago
A ball is rolling along at speed v without slipping on a horizontal surface when it comes to a hill that rises at a constant ang
MissTica

Answer:

The ball has an initial linear kinetic energy and initial rotational kinetic energy which can both be converted into gravitational potential energy. Therefore the hill with friction will let the ball reach higher.

Explanation:

The ball has an initial linear kinetic energy and initial rotational kinetic energy which can both be converted into gravitational potential energy. Therefore the hill with friction will let the ball reach higher.

This is because:

If we consider the ball initially at rest on a frictionless surface and a force is exerted through the centre of mass of the ball, it will slide across the surface with no rotation, and thus, there will only be translational motion.

Now, if there is friction and force is again applied to the stationary ball, the frictional force will act in the opposite direction to the force but at the edge of the ball that rests on the ground. This friction generates a torque on the ball which starts the rotation.

Therefore, static friction is infact necessary for a ball to begin rolling.

Now, from the top of the ball, it will move at a speed 2v, while the centre of mass of the ball will move at a speed v and lastly, the bottom edge of the ball will instantaneously be at rest. So as the edge touching the ground is stationary, it experiences no friction.

So friction is necessary for a ball to start rolling but once the rolling condition has been met the ball experiences no friction.

6 0
3 years ago
A car enters a horizontal, curved roadbed of radius 50 m. the coefficient of static friction between the tires and the roadbed i
UkoKoshka [18]
Previous results tell us the speed (v) is given in terms of the coefficient of friction (k) and the radius of the curve (r) as
  v = √(kgr)
  v = √(0.20·9.8 m/s²·50 m)
  = 7√2 m/s ≈ 9.90 m/s
6 0
3 years ago
Read 2 more answers
Other questions:
  • What is an cell described in
    5·1 answer
  • An object of mass m slides down an incline with angle 0.
    6·2 answers
  • A joule is equivalent to a
    8·1 answer
  • Shaun is 68 miles away from Keegan. They are traveling towards each other. If Keegan travels 7 mph faster than Shaun and they me
    15·1 answer
  • when we touch a steel rod and a paper simultaneously we feel that the rod is comparatively colder .why?
    13·1 answer
  • Q010) A well in which the water rises on its own to a level above its aquifer Group of answer choices is the result of pressure
    8·1 answer
  • A biker first accelerates from 0.0 m/s to 6.0 m/s in 6 s, then continues at this speed for 5 s. What is the total distance trave
    8·1 answer
  • Can you guys help me with this guestion?
    10·1 answer
  • Please help! im being timed!! urgent!
    12·1 answer
  • The mass after a physical change, such as ice melting into water, stays the same a. -true b. -false.
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!