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
liberstina [14]
3 years ago
15

A pole-vaulter is nearly motionless as he clears the bar, set 4.2 m above the ground. He then falls onto a thick pad. The top of

the pad is 80 cm above the ground, and it compresses by 50 cm as he comes to rest. What is the magnitude of his acceleration as he comes to rest on the pad?
Physics
1 answer:
Mandarinka [93]3 years ago
5 0

initial height of the Pole - vaulter = 4.2 m

now when he reached the top of the pad his height is 80 cm

so the total displacement of the person will be = 4.2 - 0.8 = 3.4 m

now we can use kinematics to find the speed just before he touch the pad

v_f^2 - v_i^2 = 2 a d

v_f^2 - 0 = 2*9.8*3.4

v_f^2 = 66.64

v_f = 8.16 m/s

now when he compressed on pad the distance after which he will stop is 50 cm

so now again using kinematics we can say

v_f^2 - v_i^2 = 2 a d

0 - 8.16^2 = 2*a*0.50

a = -66.64 m/s^2

so it is acceleration by -66.64 m/s^2

You might be interested in
A cyclist rode an average speed of 10 miles per hour for 15 miles how long was the ride
Ainat [17]
I think it's an hour and a half
7 0
3 years ago
Arm ab has a constant angular velocity of 16 rad/s counterclockwise. At the instant when theta = 60
geniusboy [140]

The <em>linear</em> acceleration of collar D when <em>θ = 60°</em> is - 693.867 inches per square second.

<h3>How to determine the angular velocity of a collar</h3>

In this question we have a system formed by three elements, the element AB experiments a <em>pure</em> rotation at <em>constant</em> velocity, the element BD has a <em>general plane</em> motion, which is a combination of rotation and traslation, and the ruff experiments a <em>pure</em> translation.

To determine the <em>linear</em> acceleration of the collar (a_{D}), in inches per square second, we need to determine first all <em>linear</em> and <em>angular</em> velocities (v_{D}, \omega_{BD}), in inches per second and radians per second, respectively, and later all <em>linear</em> and <em>angular</em> accelerations (a_{D}, \alpha_{BD}), the latter in radians per square second.

By definitions of <em>relative</em> velocity and <em>relative</em> acceleration we build the following two systems of <em>linear</em> equations:

<h3>Velocities</h3>

v_{D} + \omega_{BD}\cdot r_{BD}\cdot \sin \gamma = -\omega_{AB}\cdot r_{AB}\cdot \sin \theta   (1)

\omega_{BD}\cdot r_{BD}\cdot \cos \gamma = -\omega_{AB}\cdot r_{AB}\cdot \cos \theta   (2)

<h3>Accelerations</h3>

a_{D}+\alpha_{BD}\cdot \sin \gamma = -\omega_{AB}^{2}\cdot r_{AB}\cdot \cos \theta -\alpha_{AB}\cdot r_{AB}\cdot \sin \theta - \omega_{BD}^{2}\cdot r_{BD}\cdot \cos \gamma   (3)

-\alpha_{BD}\cdot r_{BD}\cdot \cos \gamma = - \omega_{AB}^{2}\cdot r_{AB}\cdot \sin \theta + \alpha_{AB}\cdot r_{AB}\cdot \cos \theta - \omega_{BD}^{2}\cdot r_{BD}\cdot \sin \gamma   (4)

If we know that \theta = 60^{\circ}, \gamma = 19.889^{\circ}, r_{BD} = 10\,in, \omega_{AB} = 16\,\frac{rad}{s}, r_{AB} = 3\,in and \alpha_{AB} = 0\,\frac{rad}{s^{2}}, then the solution of the systems of linear equations are, respectively:

<h3>Velocities</h3>

v_{D}+3.402\cdot \omega_{BD} = -41.569   (1)

9.404\cdot \omega_{BD} = -24   (2)

v_{D} = -32.887\,\frac{in}{s}, \omega_{BD} = -2.552\,\frac{rad}{s}

<h3>Accelerations</h3>

a_{D}+3.402\cdot \alpha_{BD} = -445.242   (3)

-9.404\cdot \alpha_{BD} = -687.264   (4)

a_{D} = -693.867\,\frac{in}{s^{2}}, \alpha_{BD} = 73.082\,\frac{rad}{s^{2}}

The <em>linear</em> acceleration of collar D when <em>θ = 60°</em> is - 693.867 inches per square second. \blacksquare

<h3>Remark</h3>

The statement is incomplete and figure is missing, complete form is introduced below:

<em>Arm AB has a constant angular velocity of 16 radians per second counterclockwise. At the instant when θ = 60°, determine the acceleration of collar D.</em>

To learn more on kinematics, we kindly invite to check this verified question: brainly.com/question/27126557

5 0
2 years ago
1. An astronaut is getting ready to explore. If his mass is 60 kg, what is his weight<br> on Earth?
kifflom [539]

Answer:

<h3>The mass of an object is the same on Earth, in orbit, or on the surface of the Moon. ... 1N=1kg ⋅m/s2. 1 N = 1 kg · m/s 2 . ... The gravitational force on a mass is its weight. ... </h3>

Explanation:

<h3>ILY:)</h3>

3 0
2 years ago
Read 2 more answers
Determine the maximum shearing stress in a solid shaft of 1.5-in. diameter as it transmits 75 hp at a speed of 1800 rpm. (Round
erma4kov [3.2K]

Answer:

\tau=3.96\ ksi

Explanation:

Given that

d= 1.5 in                      ( 1 in = 0.0254 m)

d= 0.0381 m

P= 75 hp                      ( 1 hp = 745.7 W)

P= 55927.5 W

N= 1800 rpm

We know that power P is given as

P=\dfrac{2\pi N\ T}{60}

T=Torque

N=Speed

55927.5=\dfrac{2\times \pi \times 1800\ T}{60}

T=296.85 N.m

The maximum shear stress is given as

\tau=\dfrac{16 T}{\pi d^3}

\tau=\dfrac{16\times 296.85}{\pi \times 0.0381^3}

\tau=27.35\ MPa

We know that 1 MPa =0.145 ksi

\tau=3.96\ ksi

3 0
3 years ago
PLEASE HELP ASAP!!
kolezko [41]

A. Wedge

and

B.Screw

A screw is like an inclined plane wrapped around a pole or rod.

and a wedge looks kind of looks like this / and is inclined.

Hope this helps!

Please mark me brainliest! Thanks!

5 0
3 years ago
Other questions:
  • What is a good analogy for potential energy in a circuit?
    14·1 answer
  • For the following types
    15·1 answer
  • An average person can reach a maximum height of about 60 cm when jumping straight up from a crouched position. During the jump i
    7·1 answer
  • In what form does carbon return to the atmosphere after it is released from the burning of fossil fuels
    6·1 answer
  • Particle A has less mass than particle B. Both are pushed forward across a frictionless surface by equal forces for 1 s. Both st
    9·1 answer
  • Two floors in a building are separated by 4.1 m. People move between the two floors on a set of stairs. (a) Determine the change
    15·1 answer
  • Answer in detail? Describe an activity that gives an understanding of ‘Electrostatic force’.
    5·1 answer
  • What is the difference between Helium3, and Helium?
    14·1 answer
  • Which two elements have the same number of valence electrons?<br> pls help 50 points
    6·1 answer
  • In each part calculate the kinetic energy of the given objects in joules a) an automobile whose mass is 1260kg moving at a speed
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!