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2 years ago

Find rm, the length of the moment arm of the force. express your answer in terms of l and θ.

Physics

2 answers:

Delvig [45]2 years ago

6 0

rm = r sin θ

τ = -r sin θ F

<h3>Further explanation </h3>

Torque (moment of force) with respect to the pivot point P is defined as the product of the magnitude of the force F and the moment's arm

The torque can be clockwise or counterclockwise (counterclockwise marked +, clockwise marked -)

For objects with 2 or more forces, the total torque is:

From pictures attached

τ = -rm x F

rm = (arm force which is perpendicular to the work line)

⇒ negative sign because the torque is clockwise to the point P

while the magnitude of the arm force rm:

rm = r sin θ

<h3>Learn more</h3>

tangential force

brainly.com/question/2175648

static equilibrium

brainly.com/question/13962409

Newton's Law

brainly.com/question/13725525

Alchen [17]2 years ago

3 0

Answer:

$r_m= rsin\theta$

Explanation:

from the figure in the attachment we can write

Torque about point p

$\tau=-Frsin(180-\theta)$ ( negative sign because of sign convention, out ward positive in ward ingative)

For the length r_m we can write

$Sin\theta= \frac{r_m}{r}$

therefore,

$r_m= rsin\theta$

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Answer:

Option B, 93 cm

Explanation:

An diagram of the seed's motion is attached to this solution.

This is very close to a projectile motion question. And the quantity to be calculated, how far along the grant a seed released would travel is called the Range.

And this would be obtained from the equations of motion,

First of, the height of the plant is related to some quantities of the motion with this relation.

H = u(y) t + 0.5g(t^2)

U(y) = initial vertical component of velocity = 0 m/s, H = height at which motion began, = 20cm = 0.2 m

That means t = √(2H/g)

The horizontal distance covered, R,

R = u(x) t + 0.5g(t^2) = u(x) t (the second part of the equation goes to zero as the vertical component of the acceleration of this motion is 0)

(substituting the t = √(2H/g) derived from above

R = u(x) √(2H/g)

Where u(x) = the initial horizontal component of the bomb's velocity = maximum initial speed, that is, 4.6 m/s, H = vertical height at which the seed was released = 20 cm = 0.2 m, g = acceleration due to gravity = 9.8 m/s2

R = 4.6 √(2×0.2/9.8) = 0.929 m = 0.93 m = 93 cm. Option B.

QED!

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2 years ago

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Answer:

$I=68.31\times 10^{-6}\ A$

Explanation:

Given that

J(r) = Br

We know that area of small element

dA = 2 π dr

I = J A

dI = J dA

Now by putting the values

dI = B r . 2 π dr

dI= 2π Br² dr

Now by integrating above equation

$\int_{0}^{I}dI= \int_{r_1}^{r_2}2\pi Br^2 dr$

$I={2\pi B}\times \dfrac{r_2^3-r_1^3}{3}$

Given that

B= 2.35 x 10⁵ A/m³

r₁ = 2 mm

r₂ = 2+ 0.0115 mm

r₂ = 2.0115 mm

$I={2\pi B}\times \dfrac{r_2^3-r_1^3}{3}$

By putting the values

$I={2\pi \times 2.35 \times 10^5 }\times \dfrac{(2.0115\times 10^{-3})^3-(2\times 10^{-3})^3}{3}\ A$

$I=68.31\times 10^{-6}\ A$

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2 years ago

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An activity that is relatively short in time (< 10 seconds) and has few repetitions predominately uses the _____________ ener

tensa zangetsu [6.8K]

An activity that is relatively short in time <10 seconds and has few repetitions predominantly uses the ATP/PC energy system. The cellular respiration procedure that changes food energy into ATP which is a form of energy is largely reliant on oxygen obtainability. During exercise the source and request of oxygen obtainable to muscle is unnatural by period and strength and by the individual’s cardiorespiratory suitability level.
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2. Phosphocreatine is then broken down by the enzyme creatine kinase into creatine and phosphate.

3. The energy free in the breakdown of PC permits ADP and Pi to rejoin creating more ATP. This newly made ATP can now be broken down to issue energy to fuel activity.

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2 years ago

Stu wanted to calculate the resistance of a light bulb connected to a 4.0-V battery, with a resulting current of 0.5 A. He used

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Answer:

The answer is not correct.

Explanation:

Stu's answer is not correct, the equation to use is known as the law of ohm. In which the voltage is defined as the product of the current by the resistance, then we will see this equation.

$V = I*R\\where:\\I = current [amp]\\R = resistance [ohm]\\V = voltage [volts]\\$

In order to find resistance, this term is found multiplying the current on the right side of the equation, therefore the current will be divided on the left side of the equation.

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That is the reason that the result found by Stu is not correct.

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2 years ago

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In this problem, you will analyze a system composed of two blocks, 1 and 2, of respective masses m1 and m2. To simplify the anal

Dafna1 [17]

Answer:

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Explanation:

In this problem we have two blocks and the system is formed by the two bodies.

Part A. Initially they ask us to find the moment of the whole system

p = m1 v1 + m2 v2

Part B.

Find the derivative

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dp / dt = m1 a1 + m2 a2

Part C.

Let's analyze the dimensions

m a = [kg] [m / s2] = [N]

It is equivalent to force

Part d

Acceleration is due to a net force applied

Part e

The acceleration of block 1 is due to the force exerted by block 2 during the moment change

Part f

Force of block 1 on block 2

True f12 = m1a1 f21 = m2a2

Part g

By the law of action and reaction are equal magnitude F12 = f21

Part H

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2 years ago