I'm bored. ........................

-g With what tension must a rope with length 2.50 m and mass 0.120 kg be stretched for transverse waves of frequency 40.0 Hz to

Alex17521 [72]

Answer:

43.2 N

Explanation:

$\lambda$ = Wavelength = 0.75 m

f = Frequency = 40 Hz

m = Mass of string = 0.12 kg

L = Length of string = 2.5 m

$\mu$ = Linear density = $\dfrac{m}{L}$

Velocity of wave is given by

$v=\lambda f\\\Rightarrow v=0.75\times 40\\\Rightarrow v=30\ m/s$

The tension in string is given by

$T=v^2\mu\\\Rightarrow T=30^2\times \dfrac{0.12}{2.5}\\\Rightarrow T=43.2\ N$

The tension in the string is 43.2 N

8 0

3 years ago

A force of F = (2.00ˆi + 3.00ˆj) N is applied to an object that is pivoted about a fixed axle aligned along the z coordinate axi

Vladimir [108]

Explanation:

It is given that,

Force applied to object, $F=(2i+3j)\ N$

Position, $r=(4i+5j)\ m$

(b) The cross product of force and position vector is used to find the net torque about the z axis. It is given by :

$\tau=F\times r$

$\tau=(2i+3j) \times (4i+5j)$

$\tau=\begin{pmatrix}0&0&-2\end{pmatrix}$

or

$\tau=(-2k)\ N-m$

The torque is acting in -z axis.

(a) The magnitude of torque is given by :

$|\tau|=\sqrt{(-2)^2}$

$|\tau|=2\ N-m$

Hence, this is the required solution.

5 0

3 years ago

If a 51kg snowboarder falls of a cliff, and is falling 15 m/s when they impact the snow, what is the average force of the snow o

storchak [24]

Answer:

Average force is F = mass times change in V/ change in time so..

1 366.07143 N

Explanation:

51 kg x 15 m/s / 0.56

1 366.07143 m kg / s

1 366.07143 N

1 kilogram 1 meter per second per second = 1 N

5 0

3 years ago

On a windy day, the wind turbine transfers 78 W of power. Calculate the amount of energy the turbine transfers in 10s.

tangare [24]

Answer:

Energy = 780 Joules

Explanation:

Given the following data;

Power = 78 Watts

Time = 10 seconds

To find the energy transferred;

Energy refers to the amount or quantity of power which is being consumed by an individual, group of people or organization over a specific period of time.

Mathematically, energy is given by the formula;

Energy = power * time

Energy = 78 * 10

Energy = 780 Joules

Therefore, the amount of energy the turbine transferred is 780 Joules

4 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

2 years ago