You can increase your flexiablity by streaching your bones / muscles

A person whose near-point distance is 45.5 cm wears a pair of glasses that are 2.1 cm from her eyes. With the aid of these glass

scoundrel [369]

Answer:

a

$f = 0.4848 \ m$

b

$p = 2.063 D$

Explanation:

From the question we are told that

The near point distance is $k = 45.5 \ cm$

The distance of the glasses from the eye is $y = 2.1 \ cm$

The distance of an object she can focus with the glass is $i= 25 \ cm$

Generally the image distance is mathematically evaluated as

$v = -(45.5 - 2.1)$

$v = -43.4 \ cm$

Generally the object distance is mathematically represented as

$u = (25 -2.1)$

$u = 22.9 \ cm$

The negative sign tells us that the image was formed behind the eye

Generally the lens formula is mathematically represented as

$\frac{1}{f} = \frac{1}{u} + \frac{1}{v}$

=> $\frac{1}{f} = \frac{1}{22.9} + \frac{1}{ - 43.4}$

=> $f = 48.48 \ cm$

converting to meters

$f = 0.4848 \ m$

Thus the refractive power is mathematically represented as

$p = \frac{1}{f}$

=> $p = \frac{1}{0.4848 }$

=> $p = 2.063 D$

3 0

4 years ago

7) T F If two forces of equal magnitude act on an object that is hinged at a pivot, the force acting farther from the pivot must

saul85 [17]

Answer:

False

Explanation:

The torque exerted by a force is given by:

$\tau=Fd sin \theta$

where

F is the magnitude of the force

d is the distance between the point of application of the force and the pivot

$\theta$ is the angle between the directions of F and d

We see that the magnitude of the torque depends on 3 factors. In this problem, we have 2 forces of equal magnitude (so, equal F). Moreover, one of the forces (let's call it force 1) acts farther from the pivot than force 2, so we have

$d_1 > d_2$

However, this does not mean that force 1 produces a greater torque. In fact, it also depends on the angle at which the force is applied. For instance, if the first force is applied parallel to d, then we have

$\theta_1 =0\\sin \theta=0$

and the torque produced by this force would be zero.

So, the statement is false.

4 0

3 years ago

Which of the following statements are true?

Likurg_2 [28]

Answer:

Explanation:

(A) True: It is true.

In junction law, the current entering at a junction is equal to teh current leaving at the junction.

(B) False: It is false.

The kirchhoff's junction law is based on the conservation of charge.

(C) True: It is true.

Energy is used in the circuit.

(D) True: It is true.

It is based on the conservation of charge.

4 0

3 years ago

5) A 20.0 kg cart with no friction wheels sits on a table. A light string is attached to it and runs over a low friction pulley

ella [17]

Answer:

1) Please find attached, created with Microsoft Visio

2) The acceleration of the masses connected by the light string is 0.00735 m/s²

3) The tension in the cord is 0.147 N

4) The time it would take the block to go 1.2 m to the edge of the table is approximately 18.07 s

5) The velocity of the cart as soon as it gets to the edge of the table is 0.042 m/s

Explanation:

1) Please find attached, the required free body diagram, showing the tension, weight and frictional (zero friction) forces acting on the cart and the mass created with Microsoft Visio

2) The acceleration of the masses connected by the light string is given as follows;

F = Mass, m × Acceleration, a

The mass of the truck, M = 20.0 kg

The mass attached to the string, hanging rom the pulley, m = 0.0150 kg

The force, F acting on the system = The pulling force on the cart = The tension on the cable = The weight of the hanging mass = 0.0150 × 9.8 = 0.147 N

The pulling force acting on the cart, F = M × a

∴ F = 0.147 N = 20.0 kg × a

a = 0.147 N/(20.0 kg) = 0.00735 m/s²

The acceleration of the truck = a = 0.00735 m/s²

3) The tension in the cord = F = 0.147 N

4) The time, t, it would take the block to go 1.2 m to the edge of the table is given by the kinematic equation, s = u·t + 1/2·a·t²

Where;

s = The distance to the edge of the table = 1.2 m

u = The initial velocity = 0 m/s (The cart is assumed to be initially at rest)

a = The acceleration of the cart = 0.00735 m/s²

t = The time taken

Substituting the known values, gives;

s = u·t + 1/2·a·t²

1.2 = 0 × t + 1/2 ×0.00735 × t²

1.2 = 1/2 ×0.00735 × t²

t² = 1.2/(1/2 ×0.00735) ≈ 326.5306

t = √(1.2/(1/2 ×0.00735)) ≈ 18.07

The time it would take the block to go 1.2 m to the edge of the table = t ≈ 18.07 s

5) The velocity, v, of the cart as soon as it gets to the edge of the table is given by the kinematic equation, v² = u² + 2·a·s as follows;

v² = u² + 2·a·s

u = 0 m/s

v² = 0² + 2 × 0.00735 × 1.2 = 0.001764

v = √(0.001764) = 0.042

The velocity of the cart as soon as it gets to the edge of the table = v = 0.042 m/s.

7 0

3 years ago

Read 2 more answers

PLEASE PLEASE HELP ME

SVEN [57.7K]

Microwaves are one of the lowest energies on the electromagnetic spectrum. While X-Rays are one of the highest energies on the electromagnetic spectrum. One similarity is that they are both on the electromagnetic spectrum. Also they both travel at the spped of light in a vacuum. One way they are different is They have different frequencies and wavelengths. Also they are used for different studies.

8 0

3 years ago