Does a steep plane prove more mechanical advantage than a gradual plane

A. How long (in ns) does it take light to travel 1.0 m in a vacuum?

suter [353]

Answer:

a) 3.33 ns

b) Water distance = 0.75 m

Glass distance = 0.66 m

Diamond distance = 0.41 m

Explanation:

We take the speed of light, c = m/s.

Speed = distance/time

Time = distance/speed

a)

$t=\dfrac{1}{3.0\times10^{8}}=3.33\times10^{-9}$

t = 3.33 ns

b)

Refractive index, n = speed of light in vacuum / speed of light in medium

$n=\dfrac{c}{s}$

$s=\dfrac{c}{n}$

$d=s\times t$

$d=\dfrac{c}{n}\times \dfrac{1}{c}$

$d=\dfrac{1}{n}$

Thus, the distance traveled in the same time is numerically equal to the reciprocal of the refractive index.

For water n = 1.333

d = 1/1.333 = 0.75 m

For glass n = 1.517

d = 0.66 m

For diamond n = 2.417

d = 0.41 m

4 0

3 years ago

An object experiences a 8.9 N force and accelerates 6 m/sec2. What is the object's

Inessa [10]

b stupidrwfs

planation:

3 0

3 years ago

Suppose two point charges, Q1 = +3.37 x 10^-6 C and Q2 = -8.21 x 10^-6 C, are separated by a distance d = 1.99 m.

valentina_108 [34]

Option (C) is the correct one.

Explanation:
Coulmbs law here is,

$\frac{9 \times {10}^{9} \times ( - 8.21 \times {10}^{ - 6} )(3.37 \times {10}^{ - 6} )}{ {(1.99)}^{2} } \\ \\ = - 0.0628 \\$

Which is almost equal to optionC.

8 0

3 years ago

A horizontal board of length 6.1 m and mass 12.8 kg rests on two supports. The first support is at one end of the board. The sec

Svetllana [295]

Answer:102.84 N

Explanation:

Given

Mass of board $m=12.8\ kg$

Length of board $l=6.1\ m$

First support is at one end and second support is at a distance of 2.38 m from the other end

Suppose $R_1$ and $R_2$ are the reactions at the two support

Taking moment about the first end we can write

$mg\times \dfrac{6.1}{2}-R_2(6.1-2.38)=0$

$R_2=\dfrac{12.8\times 9.8 \times 3.05}{3.72}$

$R_2=102.84\ N$

5 0

3 years ago

A ball of 0.1kg is thrown straight up into the air with

Contact [7]

a) The momentum of the ball at the maximum height is zero

b) The momentum of the ball at halfway is 1.06 kg m/s

Explanation:

a)

There is only one force acting on the ball during its motion: the force of gravity, acting downward. As a result, the ball hasa constant acceleration downward ( $g=9.8 m/s^2$ , acceleration of gravity), and therefore it is in free fall motion.

This means that the velocity of the ball is given by the equation:

$v=u-gt$

where

v is the velocity at time t

u = 15 m/s is the initial velocity

$g=9.8 m/s^2$

As we see from the equation, the term $-gt$ is negative: this means that as the ball goes higher and higher, its velocity decreases. The point of maximum height is reached when the velocity has become zero (after that point, the velocity changes direction and points downward), so when