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
Neko [114]
3 years ago
10

A rifle fires a 2.90 x 10-2-kg pellet straight upward, because the pellet rests on a compressed spring that is released when the

trigger is pulled. The spring has a negligible mass and is compressed by 8.37 x 10-2 m from its unstrained length. The pellet rises to a maximum height of 7.23 m above its position on the compressed spring. Ignoring air resistance, determine the spring constant.
Physics
2 answers:
Juliette [100K]3 years ago
8 0

Answer: 587.14 N/m

Explanation:

E(f) = E(0) such that

0.5mv(f)² + 0.5Iw(f)² + mgh(f) + 0.5ky(f)² =

0.5mv(0) + 0.5Iw(0)² + mgh(0) + 0.5ky(0)²

since the pellets does not rotate, then the angular speeds are zero, so, w(f) and w(0) = 0

Since the pellet is at rest, and sits on the Spring, the translational speed, v(0) and v(f) are zero too.

Since the Spring is not strained when it reaches maximum height, y(f) = 0, so that

mgh(f) = mgh(0) + 0.5ky(0)²

[mgh(f) - mgh(0)] / y² = 0.5k

mg[h(f) - h(0)] / y² =0.5k

(2.9*10^-2 * 9.8 * 7.23) / (8.37*10^-2)² = 0.5k

2.055 / 7*10^-3 = 0.5k

0.5k = 293.571

k = 293.571/0.5

k = 587.14 N/m

iren2701 [21]3 years ago
7 0

Answer: 586.60N/m

Explanation:

In this scenario, the elastic potential energy of the spring is converted into potential energy.

0.5*K*x^2 = mgh

Thus K = 2mgh/x^2

=(2*2.90*10^-2*9.8*7.23)/(8.37*10^-2)^2

=586.599

Therefore K = 586.60N/m

You might be interested in
What is true about energy that is added to a closed system?
Setler [38]

The correct answer is B

6 0
3 years ago
Read 2 more answers
The larger the push, the larger the change in velocity. This is an example of Newton's Second Law of Motion which states that th
Paul [167]
According to Newton, an object will only accelerate if there is a net or unbalanced forceacting upon it. The presence of an unbalanced force will accelerate an object - changing its speed, its direction, or both its speed and direction.
6 0
3 years ago
Read 2 more answers
A concave mirror has a focal length of 30.0 CM. an object is placed 15.0 CM from the mirror. what is the radius of curvature of
Nana76 [90]

Answer:

60 cm

Explanation:

We are given;

  • Focal length of a concave mirror as  30.0 cm
  • Object distance is 15.0 cm

We are required to determine the radius of curvature.

We need to know that the radius of a curvature is the radius of a circle from which the curved mirror is part.

We also need to know that the radius of curvature is twice the focal length of a curved mirror.

Therefore;

Radius of curvature = 2 × Focal length

Therefore;

Radius of curvature = 2 × 30 cm

                                 = 60 cm                                  

7 0
3 years ago
A fisherman notices that his boat is moving up and down periodically, owing to waves on the surface of the water. It takes 2.5 s
gulaghasi [49]

(a) 0.96 m/s

The period of the wave corresponds to the time taken for one complete oscillation of the boat, from the highest point to the highest point again. Since the time between the highest point and the lowest point is 2.5 s, the period is twice this time:

T=2\cdot 2.5 s=5.0 s

The frequency of the waves is the reciprocal of the period:

f=\frac{1}{T}=\frac{1}{5.0 s}=0.20 Hz

The wavelength instead is just the distance between two consecutive crests, so

\lambda=4.8 m

And the wave speed is given by:

v=\lambda f=(4.8 m)(0.20 Hz)=0.96 m/s

(b) 0.265 m

The total distance between the highest point of the wave and its lowest point is

d = 0.53 m

The amplitude is just the maximum displacement of the wave from the equilibrium position, so it is equal to half of this distance. So, the amplitude is

A=\frac{d}{2}=\frac{0.53 m}{2}=0.265 m

(c) Amplitude: 0.15 m, wave speed: same as before

In this case, the amplitude of the wave would be lower. In fact,

d = 0.30 m

So the amplitude would be

A=\frac{d}{2}=\frac{0.30 m}{2}=0.15 m

Instead, the wave speed would not change, since neither the frequency nor the wavelength of the wave have changed.

8 0
3 years ago
A 4.79 g bullet moving at 642.3 m/s penetrates a tree trunk to a depth of 4.35 cm. Use work and energy considerations to find th
vladimir1956 [14]

Answer:

Force, F=2.27\times 10^4\ N

Explanation:

Given that,

Mass of the bullet, m = 4.79 g = 0.00479 kg

Initial speed of the bullet, u = 642.3 m/s

Distance, d = 4.35 cm = 0.0435 m

To find,

The magnitude of force required to stop the bullet.

Solution,

The work energy theorem states that the work done is equal to the change in its kinetic energy. Its expression is given by :

F.d=\dfrac{1}{2}m(v^2-u^2)

Finally, it stops, v = 0

F.d=-\dfrac{1}{2}m(u^2)

F=\dfrac{-mu^2}{2d}

F=\dfrac{-0.00479\times (642.3)^2}{2\times 0.0435}

F = -22713.92 N

F=2.27\times 10^4\ N

So, the magnitude of the force that stops the bullet is 2.27\times 10^4\ N

7 0
3 years ago
Other questions:
  • An electron, moving south, enters a magnetic field of certain strength. Because of this field the electron curves upward. What i
    9·1 answer
  • Which statement best describes the circular flow model?
    13·1 answer
  • An 80 kilogram skier slides on waxed skis along a horizontal surface of snow at a constant velocity while pushing with his poles
    12·1 answer
  • What is the output voltage from a step up transformer with 25 turns in the primary coil and 75 turns in the secondary coil if th
    13·1 answer
  • For comparison, what is the magnitude of the acceleration a test tube would experience if dropped from a height of 1.0 m and sto
    6·1 answer
  • How does the tilt of the earth affect climate?
    15·1 answer
  • Convert 41.3 kilocalories into joules.
    5·1 answer
  • How much work does a 60kg person do in walking up 5m of stairs
    14·1 answer
  • A 75 kg astronaut floating in space throws a 5 kg rock at 5 m/sec. How fast does the astronaut move backwards?
    14·1 answer
  • What are the factor affecting the moment of force
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!