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
wel
3 years ago
6

3 points

Physics
1 answer:
blagie [28]3 years ago
8 0

Answer:

A and D

Explanation:

Acceleration is the active change in speed, increasing or decreasing.

You might be interested in
A 73-kg Norwegian olympian ski champion is going down a hill sloped at 39 ◦ . The coefficient of kinetic friction between the sk
bazaltina [42]

Answer:

Explanation:

net force on the skier = mg sin 39 - μ mg cos39

mg ( sin39 - μ cos39 )

= 73 x 9.8 ( .629 - .116)

= 367 N

impulse = net force x time = change in momentum .

= 367 x 5 = 1835 kg m /s

velocity of the skier after 5 s = 1835 / 73

= 25.13 m /s

b )

net force becomes zero

mg ( sin39 - μ cos39 ) = 0

μ = tan39

= .81

c )

net force becomes zero , so he will continue to go ahead with constant speed of 25.13 m /s

so he will have speed of 25.13 m /s after 5 s .

5 0
3 years ago
The wave length of violet light rounded to the nearest nanometer is a __ nm
nataly862011 [7]
Wavelength= speed / frequency 

so.....3× 10^8 / 7.26×10^14
= .413× 10^(-6)

in scientific notation= 4.13×10^(-7) 

in nanometer = 413 nm
6 0
3 years ago
How do motors use energy? Do they convert electrical energy into mechanical energy OR mechanical energy into electrical energy?
Marysya12 [62]

Answer:

Motors convert electrical energy into mechanical energy

Explanation:

A motor uses electrical energy to create mechanical energy by creating magnetic fields causing the motor to spin. A generator is the opposite and converts mechanical into electrical by spinning a motor in a magnetic field.

3 0
2 years ago
Read 2 more answers
A free positive charge released in an electric field will:
choli [55]

Answer:

accelerate in the direction in which the electric field is pointing.

Explanation:

The positive charge feels a force in the same direction as the electric field

F=Eq  

F and E are vectors, q is a scalar

(if it were a negative charge the force would be in the opposite direction)

that force will produce an acceleration in the same direction, that acceleration will cause the particle to move in the same direction, ie the direction of the electric field.

7 0
3 years ago
The current theory of the structure of the
IRISSAK [1]

1) The mass of the continent is 3.3\cdot 10^{21} kg

2) The kinetic energy of the continent is 624 J

3) The speed of the jogger must be 4 m/s

Explanation:

1)

We start by finding the volume of the continent. We have:

L = 5850 km = 5.85\cdot 10^6 m is the side

t = 35 km = 3.5\cdot 10^4 m is the depth

So the volume is

V=L^2 t = (5.85\cdot 10^6)^2 (3.5\cdot 10^4)=1.20\cdot 10^{18} m^3

We also know that its density is

d=2750 kg/m^3

Therefore, we can find the mass by multiplying volume by density:

m=dV=(2750)(1.20\cdot 10^{18})=3.3\cdot 10^{21} kg

2)

The kinetic energy of the continent is given by:

K=\frac{1}{2}mv^2

where

m=3.3\cdot 10^{21} kg is its mass

v = 3.2 cm/year is the speed

We have to convert the speed into m/s. We have:

3.2 cm = 0.032 m

1 year = 1(365)(24)(60)(60)=3.15\cdot 10^7 s

So, the speed is:

v=\frac{0.032 m}{3.15 \cdot 10^7 s}=1.02\cdot 10^{-9} m/s

So, we can now find the kinetic energy:

K=\frac{1}{2}(1.20\cdot 10^{21})(1.02\cdot 10^{-9})^2=624 J

3)

Here we have a jogger of mass

m = 78 kg

And the jogger has the same kinetic energy of the continent, so

K = 624 J

The kinetic energy of the jogger is given by

K=\frac{1}{2}mv^2

where v is the speed of the jogger.

Solving for v, we find the speed that the jogger must have:

v=\sqrt{\frac{2K}{m}}=\sqrt{\frac{2(624)}{78}}=4 m/s

Learn more about kinetic energy:

brainly.com/question/6536722

#LearnwithBrainly

3 0
3 years ago
Other questions:
  • An athlete always runs before taking a jump . why?
    6·1 answer
  • Which of the following is a physical change? burning a piece of wood rust forming on an iron fence sawing a piece of wood in hal
    6·1 answer
  • A dependent variable is also called a _____?
    13·1 answer
  • What is 1000 N in kilograms
    10·1 answer
  • The 3.0 kg object below is released from rest at a height of 5.0 m on a curved frictionless ramp. At the foot of the ramp is a s
    14·1 answer
  • ¿Alguien me puede ayudar? Problema: Un niño le pide gastada a su papá y éste le contesta que le dará los $120 que tiene en su bo
    15·1 answer
  • For a particular type of motion, the velocity is zero but the speed is a nonzero quantity. Which statement can you make about th
    5·1 answer
  • Two capacitors, a 15 micro F and a 25 micro F, are connected in parallel to a 60 Hz source. The total capacitive reactance is :_
    13·1 answer
  • THIS IS MY EXAM HURRY PLS
    14·2 answers
  • Two objects of masses m1 = 0.56 kg and m2 = 0.88 kg are placed on a horizontal
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!