A student is given a sample of matter and asked to determine whether it is an element.

A 0.46-kg cord is stretched between two supports, 7.2 m apart. When one support is struck by a hammer, a transverse wave travels

Kryger [21]

Answer:

T = 6.0 N

Explanation:

given,

mass of the cord = 0.46 Kg

length of the supports = 7.2 m

time taken to travel = 0.74 s

tension in the chord = ?

using formula for tension calculation

$T = \dfrac{v^2.m}{l}$

$v = \dfrac{l}{s}$

$v = \dfrac{7.2}{0.74}$

v = 9.73 m/s

now, calculation of tension

$T = \dfrac{9.73^2\times 0.46}{7.2}$

T = 6.0 N

The tension in the cord is equal to 6.0 N.

7 0

3 years ago

A student's life was saved in an automobile accident because an airbag expanded in front of his head. If the car had not been eq

dexar [7]

Answer:

Compared to windshield the airbag exerts much lesser force

Explanation:

Impulse is defined as change in momentum of the object when it is acted upon by a force during interval of time

Impulse = Impulsive force *time

I = F*Δt

If the object should be bought to rest from certain velocity there should be change in momentum. If the duration in which the momentum is increased then there would be less force applied and hence less damage.

Airbags are used to reduce the force experience by the people when they are met with accident by extending the time required to stop the momentum.

During the collision, the passenger is carried towards the windshield and if they are stopped by collision with wind shield the force will be larger and more damage.But if they are hit with airbag then the force will be less due to increased time.

The change is momentum will be the same with or without momentum but its the time that decides the impact of force.By making it longer the force become less.

Thus compared to the windshield the airbag exerts much lesser force.

 

8 0

3 years ago

What is v^2=0.05-4.9 please i need this asap

Margaret [11]

Answer:

v =2.02

Explanation:

v^2=0.05-4.9

v^2=-4.85

square root both side

v=2.02

^^^^this is a not a perfect square

7 0

3 years ago

A coil has 400 turns and self-inductance 7.50 mH. The current in the coil varies with time according to i = 1680 mA2 cos [πt/(0.

zhannawk [14.2K]

Answer:

(a) 1.58 V

(b) 0.0126 Wb

(c) 0.0493 V

Solution:

As per the question:

No. of turns in the coil, N = 400 turns

Self Inductance of the coil, L = 7.50 mH = $7.50\times 10^{- 3}\ H$

Current in the coil, i = $1680cos[\frac{\pi t}{0.0250}]$ A

where

$i_{max} = 1680\ mA = 1.680\ A$

Now,

(a) To calculate the maximum emf:

We know that maximum emf induced in the coil is given by:

$e = \frac{Ldi}{dt}$

$e = L\frac{d}{dt}(1680)cos[\frac{\pi t}{0.0250}]$

$e = - 7.50\times 10^{- 3}\times \frac{\pi}{0.0250}\times \frac{d}{dt}(1680)sin[\frac{\pi t}{0.0250}]$

For maximum emf, $sin\theta$ should be maximum, i.e., 1

Now, the magnitude of the maximum emf is given by:

$|e| = 7.50\times 10^{- 3}\times 1680\times 10^{- 3}\times \frac{\pi}{0.0250} = 1.58\ V$

(b) To calculate the maximum average flux,we know that:

$\phi_{m, avg} = L\times i_{max} = 7.50\times 10^{- 3}\times 1.680 = 0.0126\ Wb$

(c) To calculate the magnitude of the induced emf at t = 0.0180 s:

$e = e_{o}sin{\pi t}{0.0250}$

$e = 7.50\times 10^{- 3}\times sin{\pi \times 0.0180}{0.0250} = 2.96\times 10^{- 4} =0.0493\ V$

7 0

3 years ago

In which scenario is an animal doing work? Check all that apply.

AleksAgata [21]

Answer:

I think the letter B is a good idea for me to do the same as oneroure oneroure I I was just wondering if you could give me a a little more about what you are looking for in a career in the area of the main crop between the rows of the main crop between the rows of the main crop between the between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop main crop between the between the rows of rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between the rows of the main crop between a single one or more and then you have the right one for your hair that fits your hair and you are not the one to choose from the given choice of the following proof choose your own style or the color of your a color scheme that is used in used color and colors and colors of your company name what you want and how you can easily find the perfect fit in a wide range of colors the colors colors you choose want for the following elements to make sure your style is style fits into your design or and how your design is design in your style style design and color style design and color style design design and style design for your wedding photography studio design and photography studio design studio photography gallery featuring a wide web design gallery and photo design gallery design and design gallery and photo design and design studio photography studio design and photography studio photography photography photography photography photography gallery photography photography photography studio wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding photography wedding wedding photography

6 0

2 years ago