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
Sauron [17]
3 years ago
8

On his way to class, a student on a skateboard is accelerating on a downhill stretch. Which of the following statements is true?

(Select all that apply.)
A.The skateboarder's acceleration is perpendicular to the net force.
B.The skateboarder is moving in the direction of the net force.
C.The skateboarder's acceleration is in the direction of the net force.
D.The skateboarder is subjected to a net external force in the direction of motion.
Physics
1 answer:
sasho [114]3 years ago
3 0

Answer:

B is correct

Explanation:

Because of gravity

You might be interested in
A boy and a girl are on a spinning merry-go-round. The boy is at a radial distance of 1.2 m from the central axis; the girl is a
Licemer1 [7]

Answer:

E) True. The girl has a larger tangential acceleration than the boy.

Explanation:

In this exercise they do not ask us to say which statement is correct, for this we propose the solution to the problem.

Angular and linear quantities are related

          v = w r

          a = α r

the boy's radius is r₁ = 1.2m the girl's radius is r₂ = 1.8m

as the merry-go-round rotates at a constant angular velocity this is the same for both, but the tangential velocity is different

          v₁ = w 1,2 (boy)

          v₂ = w 1.8 (girl)

whereby

          v₂> v₁

reviewing the claims we have

          a₁ = α 1,2

          a₂ = α 1.8

          a₂> a₁

A) False. Tangential velocity is different from zero

B) False angular acceleration is the same for both

C) False. It is the opposite, according to the previous analysis

D) False. Angular acceleration is equal

E) True. You agree with the analysis above,

8 0
3 years ago
A projectile is fired with an initial velocity of 120.0 meters per second at an angle, θ above the horizontal. If the projectile
k0ka [10]

Answer:

θ = 62.72°

Explanation:

The projectile describes a parabolic path:

The parabolic movement results from the composition of a uniform rectilinear motion (horizontal ) and a uniformly accelerated rectilinear motion of upward or downward motion (vertical ).

The equation of uniform rectilinear motion (horizontal ) for the x axis is :

x = x₀+ vx*t   Formula (1)

vx = v₀x

Where:  

x: horizontal position in meters (m)

x₀: initial horizontal position in meters (m)

t : time (s)

vx: horizontal velocity  in m/s

v₀x: Initial speed in x  in m/s

The equations of uniformly accelerated rectilinear motion of upward (vertical ) for the y axis  are:

y= y₀+(v₀y)*t - (1/2)*g*t² Formula (2)

vfy= v₀y -gt Formula (3)

Where:  

y: vertical position in meters (m)  

y₀ : initial vertical position in meters (m)  

t : time in seconds (s)

v₀y: initial  vertical velocity  in m/s  

vfy: final  vertical velocity  in m/s  

g: acceleration due to gravity in m/s²

Data

v₀ = 120 m/s  , at an angle  θ above the horizontal

v₀x= 55 m/s

x-y components of the initial  velocity ( v₀)

v₀x = v₀*cosθ Equation (1)

v₀y = v₀*sinθ   Equation (2)

Calculating of the angle θ

We replace data in the  Equation (1)

55 =  120*cosθ

cosθ = 55 / 120

\theta = cos^{-1}(  \frac{55}{120} )

θ = 62.72°

3 0
3 years ago
You are riding a bicycle. If you apply a forward force of 150 N, and you and the bicycle have a combined mass of 90 kg, what wil
bekas [8.4K]
<h3>Hello There!!</h3>

<h3><u>Given</u>,</h3>

Force(F) = 150N

Mass(m) = 90kg

<h3><u>To </u><u>Find,</u></h3>

Acceleration(a) = ?

<h3><u>We know,</u></h3>

F= m×a

150 = 90 \times  \text{a} \\  \\  \text{a} =  \frac{150}{90}  \\  \fbox{cancelling by 3} \\  \\   \text{ a}  = \cancel \frac{150}{90} \\  \\ \text{ a}  =  \frac{5}{3}  = 1.67 \text{m/s} {}^{2}

\therefore  \text{Option A= 1.67 m/s² is the correct answer}

<h3>Hope this helps</h3>
6 0
2 years ago
An unstrained horizontal spring has a length of 0.31 m and a spring constant of 220 N/m. Two small charged objects are attached
Kruka [31]
The solution you should use is Hooke's law: F=-kx

It should have the same signs because they repel due to the stretch of the spring. 

a. Since there is a constant energy within the spring, then Hooke's law will determine the possible algebraic signs. The solution should be 
<span>F = kx 
270 N/m x 0.38 m = 102.6 N 
</span>
b. Then use Coulomb's law; F=kq1q2/r^2 to find the charges produced in the force. 



8 0
3 years ago
Block B has mass 6.00 kg and sits at rest on a horizontal, frictionless surface. Block A has mass 2.50 kg and sits at rest on to
zzz [600]

Answer:

Explanation:

Block A sits on block B and force is applied on block A . Block A will experience two forces 1) force P and 2 )  friction force in opposite direction of motion . Block B will experience one force that is force of friction in the direction of motion .

Let force on block A be P . friction force on it will be equal to kinetic friction, that is μ mg , where μ is coefficient of friction and m is mass of block A

friction force = .4 x 2.5 x 9.8

= 9.8 N

net force on block A = P - 9.8

acceleration = ( P - 9.8 ) / 2.5

force on block B = 9.8

acceleration = force / mass

= 9.8 / 6

for common acceleration

( P - 9.8 ) / 2.5  = 9.8 / 6

( P - 9.8 ) / 2.5 = 1.63333

P = 13.88 N .

4 0
3 years ago
Other questions:
  • A circuit component with a high resistance will have a low electric current.
    7·1 answer
  • Name two types of small bodies that are found on the Kuiper belt.
    9·1 answer
  • Which statement is true? Hydroelectric power is generated from moving water. Oil, a renewable resource, is processed to make jet
    14·2 answers
  • A circular curve of radius 150 m is banked at an angle of 15 degrees. A 750-kg car negotiates the curve at 85.0 km/h without ski
    11·1 answer
  • A piano tuner uses a tuner to create a tone of 5.00 x 10² Hz. When a key on the piano is struck he hears 5 beats per second. Wha
    15·1 answer
  • The magnetic flux through a coil of wire containing two loops changes at a constant rate from -83 Wb to 82 Wb in 0.39 s .
    15·1 answer
  • It would be appreciated if all questions were answered and have shown work. :)
    11·2 answers
  • Parallel rays of monochromatic light with wavelength 582 nm illuminate two identical slits and produce an interference pattern o
    13·1 answer
  • Two children are pulling on opposite sides of a blanket. The brother is pulling with a force of 3 N. The sister is pulling with
    5·1 answer
  • The acceleration of gravity on the moon is about 1.6 m/sec2. An experiment to test gravity compares the time it takes objects to
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!