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
Marysya12 [62]
3 years ago
12

Calculate the final velocity right after a 117 kg rugby player who is initially running at 7.45 m/s collides head‑on with a padd

ed goalpost and experiences a backward force of 17700 N for 5.50×10−2 s
Physics
1 answer:
Free_Kalibri [48]3 years ago
5 0

Answer:

v_f = 0.87 m/s

Explanation:

We are given;

F_avg = -17700 N (negative because it's backward)

m = 117 kg

Δt = 5.50 × 10^(−2) s

v_i = 7.45 m/s

Now, formula for impulse is given by;

I = F•Δt = - 17700 x 5.50 × 10^(−2) = - 973.5 kg.m/s

From impulse momentum theory, we know that;

Change in momentum of particle is equal to impulse.

Thus,

Δp = I = m•v_f - m•v_i

Thus,

-973.5= 117(v_f - 7.45)

Thus,

-973.5/117 = (v_f - 7.45)

-8.3205 + 7.45 = v_f

v_f = - 0.87 m/s

We'll take absolute value as;

v_f = 0.87 m/s

You might be interested in
Dentify the following terms associated with the water cycle.
vivado [14]

Answer:

condensation, precipitation, evaporation, transpiration

Explanation:

condensation is when gas condenses into liquid, precipitation is when water comes from the sky like in rain, evaporation is when water is converted from liquid to gas, transpiration is when water is evaporated from leaves.

4 0
3 years ago
A copper wire is 1.6 m long and its diameter is 1.1 mm. If the wire hangs vertically, how much weight (in N) must be added to it
qaws [65]

Answer:

Weight required = 194.51 N

Explanation:

The elongation is given by

            \Delta L=\frac{PL}{AE}

Length , L= 1.6 m

Diameter, d = 1.1 mm

Area

   A=\frac{\pi d^2}{4}=\frac{\pi \times (1.1\times 10^{-3})^2}{4}=9.50\times 10^{-7}m^2

Change in length, ΔL = 2.8 mm = 0.0028 m

Young's modulus of copper, E = 117 GPa = 117 x 10⁹ Pa

Substituting,

      \Delta L=\frac{PL}{AE}\\\\0.0028=\frac{P\times 1.6}{9.50\times 10^{-7}\times 117\times 10^9}\\\\P=194.51N

Weight required = 194.51 N

8 0
3 years ago
A box is pushed to the right with a force of 5N and at the same time it is pushed with a force of 3.6 N to the left. If the box
Aliun [14]

Answer: a= 0.175 m/s²

Explanation: To solve for acceleration we will use Newton's Second Law of Motion which is F=ma. Since there are multiple forces acting on the object, we need to summate the forces involved. Derive to find acceleration.

a= F/m

= 5 N - 3.6 N / 8 kg

= 0.175 m/s²

8 0
3 years ago
As you know, a common example of a harmonic oscillator is a mass attached to a spring. In this problem, we will consider a horiz
Eddi Din [679]

a)E= U + K = \frac{1}{2}kx² +  \frac{1}{2}mv²

The total energy of the system at any point in the motion is equal to the sum of the elastic potential energy of the spring, U, and of the kinetic energy of the mass, K:

E= U + K = \frac{1}{2}kx² +  \frac{1}{2}mv²

where

'k' represents the spring constant

'x' is the compression/stretching of the spring with respect to its equilibrium position

'm' is the mass of the block attached to the spring

and 'v' is the speed of the block

b) <em>A=</em>\sqrt{\frac{2E}{k}}<em> </em>

The amplitude of the motion compares to the most extreme displacement of the mass-spring system. The displacement of the system, x(t), at time t, for a simple harmonic oscillator is given by,

x= Asin(ωt+∅)

where

amplitude  is 'A'

\omega=\sqrt{\frac{k}{m}} is the angular frequency of the motion

t is the time

\phi is the phase (we can take \phi=0 )

The amplitude of the motion occurs when the displacement of the motion is maximum: x=A. Regarding energy, the mass-spring system is at its maximum displacement (x=A) when all the mechanical energy of the framework is elastic potential energy, so when the kinetic energy is zero:

K=\frac{1}{2}mv^2=0

E=\frac{1}{2}kA^2\\ -->(1)

<em>A=</em>\sqrt{\frac{2E}{k}}<em> </em>

c)v_{max}=\omega A<u></u>

When the elastic potential energy is zero, the maximum speed of the system occurs i.e U=0 and the kinetic energy is maximum, so:

U=0

E=\frac{1}{2}mv_{max}^2

According to the law of conservation of the mechanical energy, this energy must be equal to the energy of the system at its maximum displacement (1), so we can write

\frac{1}{2}kA^2=\frac{1}{2}mv_{max}^2

and solving for v_{max}we find an expression for the maximum speed:

v_{max}=\sqrt{\frac{kA^2}{m}}=\sqrt{\frac{k}{m}}A=\omega A

<h2><u></u>v_{max}=\omega A<u></u></h2>
4 0
3 years ago
In the steps of the scientific method, what is the next step after formulating and objectively testing hypotheses?
Dmitriy789 [7]

Answer:

Option A

interpreting results

Explanation:

In a Scientific research, we first formulate and test hypothesis of the study. A hypothesis is a tentative guess in the study which should be validated in the process of the study. We may have a null and alternative hypothesis. After formulating the study, we conduct the actual study where we get raw data. The raw data is then analyzed, in many cases using statistical analysis tools such as R, python, excel spreadsheet etc. Therefore, the next step after formulating and objectively testing hypotheses is to interpret the results.

3 0
3 years ago
Other questions:
  • The kinetic energy of a car of mass 180kg moving at a constant velocity is 4410J. What is its velocity?
    14·1 answer
  • What was the significance of the double-slit experiment? A. It showed that light had wave properties. B. It first demonstrated t
    8·1 answer
  • Please help!!!!! :)
    7·2 answers
  • An electron has _____
    9·2 answers
  • PLEASE ANSWER FIRST GETS BRAINLIEST
    10·2 answers
  • 15. An insect lands on a compact disc that is put
    15·1 answer
  • You need to repair a broken fence in your yard. The hole in your fence is around 3 meters in length and for whatever reason, the
    10·1 answer
  • Two charges A and B are fixed in place, at different distances from a certain spot. At this spot the potentials due to the two c
    14·1 answer
  • An air capacitor is made by using two flat plates, each with area A, separated by a distance d. Then a metal slab having thickne
    6·1 answer
  • a spring is compressed then launches a block vertically. The spring is compressed 15 cm and has a spring constant of 342 N/m. If
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!