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
STALIN [3.7K]
3 years ago
14

a 1 gram spiders sits on a platform rotating at 78 rpm. the spider is 15 cm from the centre disk. find the speed of the spider

Physics
1 answer:
olga nikolaevna [1]3 years ago
8 0

The spider is traveling in a circle with radius = 15cm

The circumference of any circle = <em>2 pi (radius)</em>
The circumference of the spider's path = 2 pi (15 cm) = 30 pi cm

The spider completes a trip around this path 78 times per minute.
Its speed, relative to you, is   

                               (78) x (30 pi) cm/min =

                                       2,340 pi cm/min =  7,351.33 cm/min =

                                     <em>  73.5133 meter/min =</em>

                                       <em>4.411 km/hr =</em>

                                         <em>2.74  miles/hour

</em>
(After the last appearance of pi,
all numbers are rounded.)<em>

</em>
You might be interested in
A balance is best used to measure a sample’s
blondinia [14]
The answer is “ Mass “
7 0
3 years ago
Holes are being steadily injected into a region of n-type silicon (connected to other devices, the details of which are not impo
Tems11 [23]

Complete Question

The  complete question is shown on the first  uploaded image

Answer:

The  value  is  J_n  =  -0.864 \  A/cm^2

Explanation:

Generally for an n-type semiconductor the current density is mathematically represented  as

         J_n  =  -q * d_p  *  \frac{d p_{n_o}}{d_w}

Here  p_{n_o} is mathematically represented as

          p_{n_o}  = \frac{n_i^2}{n_d}

=>      p_{n_o}  = \frac{(1.5*10^{10})^2}{10^{16}}

=>      p_{n_o}  = 2.25 *10^{4} \  cm^{-3}

So

    d p_{n_o} =  P_n0 - p_{n_o}

From the diagram  P_n0  =  10^8 * p_{n_o}

=>  P_n0  =  10^8 * (2.25 *10^{4} )

So

   d p_{n_o} =  10^8 * (2.25 *10^{4} ) - 2.25 *10^{4}

      d p_{n_o} =  2.25 *10^{12} cm^{-3}

So  from  J_n  =  -q * d_p  *  \frac{d p_{n_o}}{d_w}

substitute

    1.60 *10^{-19} \  C for  q  and  w_2 =50 nm =  50*10^{-9} m  =  5*10^{-6} cm

and from the diagram  w_1 =0 \ cm

So

    J_n  =  -1.60 *10^{-19} *12 *  \frac{2.25 *10^{12} }{ 5*10^{-6} - 0 }

    J_n  =  -0.864 \  A/cm^2

6 0
3 years ago
Click on the reset button, and stack one 50kg. crate on top of the other, so that the total mass is 100kg. The Friction should b
Helen [10]

Answer:

490.5 N

Explanation:

Coefficient of friction is 0.5 since friction force is set to halfway between none and lots. Minimum force is given by multiplying the weight and coefficient of friction

F= kN where k is coefficient of friction while N is weight. Also, N=mg where m is mass and g is acceleration due to gravity.

F=kmg=0.5*100*9.81=490.5 N

6 0
3 years ago
17 points
const2013 [10]

The velocity of the cannonball is 150 m/s,  the right option is B. 150 m/s.

The question can be solved, using Newton's second law of motion.

Note: Momentum of the cannon = momentum of the cannonball.

<h3>Formula:</h3>
  • MV = mv................. Equation 1

<h3>Where:</h3>
  • M = mass of the cannon
  • m = mass of the cannonball
  • V = velocity of the cannon
  • v = velocity of the cannonball

Make v the subject of the equation.

  • v = MV/m................ Equation 2

From the question,

<h3>Given: </h3>
  • M = 500 kg
  • V = 3 m/s
  • m = 10 kg.

Substitute these values into equation 2.

  • v = (500×3)/10
  • v = 150 m/s.

 

Hence, The velocity of the cannonball is 150 m/s,  the right option is B. 150 m/s.

Learn more about Newton's second law here: brainly.com/question/25545050

3 0
2 years ago
A swift blow with the hand can break a pine board. As the hand hits the board, the kinetic energy of the hand is transformed int
Stells [14]

Answer:

A. The hand must move with a velocity of 6.98 m/s to break the board.

B. Average force on the hand = 1025 N

Explanation:

A.To determine the speed the hand must move with to break the board, the force workdone in breaking the board is found first.

Workdone = force × distance

Minimum force required = 870 N;

Distance moved by board/Deflection in order to break = 1.4 cm = 0.014 M

Workd done = 870 N × 0.014 m = 12.18 Nm or 12.18 J

This work done = Kinetic energy of the hand

Kinetic energy = mv²/2 ; where m is mass and v is velocity

Mass of hand = 0.50 Kg, velocity = ?, K.E. = 12.18 J

v² = 2 KE/m

v = √2KE/m

v = √(2 × 12.18/0.50)

v = 6.98 m/s

Therefore, the hand must move with a velocity of 6.98 m/s to break the board.

B. Average force on the hand

This can be determined using the equation of motion, v² = u² + 2as to find acceleration, since force = mass × acceleration

From the equation of motion, a = v² - u²/2s

At rest, v = 0, u = 6.98, s = 1.2 cm = 0.012 m

a = 0² - 6.98²/ 2 × 0.012

a = -2030 m/s²

Force = 2030 m/s² × 0. 50 kg = 1015 N

Therefore, Average force on the hand = 1025 N

3 0
3 years ago
Other questions:
  • From the edge of a roof you throw a snowball downward that strikes the ground with 100J of kinetic energy. then you throw a seco
    13·1 answer
  • Is nuclear fission hybrid physics or geothermal phsics
    15·2 answers
  • In each case, you should demonstrate how you worked out your answer, as well as giving the answer.
    15·2 answers
  • Kat driving 55 mph approaching a stop light. It takes her 15 seconds to completley atop at the stop light. what was her accelera
    9·1 answer
  • What is the main cause of erosion
    7·2 answers
  • How many ternary strings of length 2 n are there in which the zeroes appear only in odd-numbered positions?
    7·1 answer
  • A boy is exerting a force of 70 N at a 50-degree angle on a lawn mower. He is accelerating at 1.8 m/s2. Round the answers to the
    8·1 answer
  • Two boats are operating in the same general area. who is responsible for avoiding a collision?
    13·2 answers
  • When the temperature of a gas decreases at constant volume, its a. pressure increases. b. mass increases. c. pressure decreases.
    7·1 answer
  • Please help<br>What is the angle of the reflected ray in the diagram above?​
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!