Is mechanical advantage always greater than one?

Light that has a wavelength of 600 nm strikes a metal surface, and a stream of electrons is ejected from the surface. If light o

Anni [7]

Answer:

The maximum kinetic energy of the electrons emitted from the surface will be greater.

Option 3 is correct.

Explanation:

Given that,

Wavelength $\lambda_{1}=600\ nm$

Wavelength $\lambda_{2}=500\ nm$

We need to calculate the energy for first wavelength

Using formula of energy

$E=hf$

$E=h\dfrac{c}{\lambda}$

Put the value into the formula

$E_{1}=6.67\times10^{-34}\times\dfrac{3\times10^{8}}{600\times10^{-9}}$

$E_{1}=3.33\times10^{-19}\ J$

We need to calculate the energy for second wavelength

Put the value into the formula

$E_{2}=6.67\times10^{-34}\times\dfrac{3\times10^{8}}{500\times10^{-9}}$

$E_{2}=4.002\times10^{-19}\ J$

So, E₂>E₁

Hence, The maximum kinetic energy of the electrons emitted from the surface will be greater.

8 0

3 years ago

Two students, standing on skateboards, are initially at rest, when they give each other a shove! After the shove, one student (7

Elden [556K]

Answer:

The other student (59kg) moves right at 7.44 m/s

Explanation:

Given;

mass of the first student, m₁ = 77kg

mass of the second student, m₂ = 59kg

initial velocity of the first student, u₁ = 0

initial velocity of the second student, u₂ = 0

final velocity of the first student, v₁ = 5.7 m/s left

final velocity of the second student, v₂ = ? right

Apply the principle of conservation of linear momentum;

Total momentum before collision = Total momentum after collision

m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂

(77 x 0) + (59 x 0) = (-77 x 5.7) + (59 x v₂)

0 = - 438.9 + 59v₂

59v₂ = 438.9

v₂ = 438.9 / 59

v₂ = 7.44 m/s to the right

Therefore, the other student (59kg) moves right at 7.44 m/s

6 0

3 years ago

Why is using two thin blankets in bed usually warmer than one thick one?

Korolek [52]

I think it is because a big thick blanket has more room in it. if you have two thin blankets there isn't a whole lot there so it keeps the warmth in. <span />

4 0

4 years ago

Read 2 more answers

A firecracker in a coconut blows the coconut into three pieces. Two pieces of equal mass fly off south and west, perpendicular t

Lisa [10]

Explanation:

Let us assume that piece 1 is $m_{1}$ is facing west side. And, piece 2 is $m_{2}$ facing south side.

Let $m_{1} \text{and} m_{2}$ = m and $m_{3}$ = 2m. Hence,

$2mv_{3y} = m(21)$

$v_{3y} = \frac{21}{2}$

= 10.5 m/s

$2mv_{3x} = m(21)$

$v_{3x} = \frac{21}{2}$

= 10.5 m/s

$v_{3} = \sqrt{v^{2}_{3x} + v^{2}_{3y}}$

= $\sqrt{(10.5)^{2} + (10.5)^{2}}$

= 14.84 m/s

or, = 15 m/s

Hence, the speed of the third piece is 15 m/s.

Now, we will find the angle as follows.

$\theta = tan^{-1} (\frac{v_{3y}}{v_{3x}})$

= $tan^{-1}(\frac{10.5}{10.5})$

= $tan^{-1} (45^{o})$

= $45^{o}$

Therefore, the direction of the third piece (degrees north of east) is north of east.

5 0

4 years ago

Tiana jogs 1.5 km along a straight path and then turns and jogs 2.4 km in the opposite direction. She then turns back and jogs 0

vichka [17]

Answer:

Distance: 4.6km Displacement= -0.2km

Explanation:

Total distance: 1.5+2.4+0.7= 4.6 km

Displacement: 1.5-2.4+0.7= -0.2km

The displacement may also be 0.2km, it just depends on if it wants it negative or not.

7 0

4 years ago