Which statement about moons is incorrect?

If the torque required to loosen a nut that

liraira [26]

Explanation:

τ = Fr

34 Nm = F (0.30 m)

F ≈ 113 N

7 0

2 years ago

A floating ice block is pushed through a displacement d = (13.5 m)i + (-14.3 m)j along a straight embankment by rushing water, w

fredd [130]

To solve this problem, we are going to use the formula for work which is Fd where x and y are measured separately.

X direction: W = 13.5 x 230 = 3105 Joules

Y direction: W = -14.3 x -165 = 2360 Joules

So the total work is getting the sum of the two: 3105 + 2360 = 5465 Joules

7 0

3 years ago

When a flat slab of transparent material is placed under water, the critical angle for light traveling from the slab into water

Novosadov [1.4K]

Answer:

(a) 40.6 degree

Explanation:

When refraction takes place from slab to water, the critical angle is 60 degree.

Use Snell's law

refractive index of water with respect to slab

$\mu _{w}^{s}=\frac{Sin60}{Sin90}$

$\frac{\mu _{w}}{\mu _{s}}=0.866$

$\frac{1.33}{\mu _{s}}=0.866$

μs = 1.536

Now for slab air interface, the critical angle is C.

$\mu _{a}^{s}=\frac{SinC}{Sin90}$

$\frac{\mu _{a}}{\mu _{s}}=\frac{SinC}{Sin90}$

1 / 1.536 = Sin C

C = 40.6 degree

3 0

2 years ago

Two ice skaters, Paula and Ricardo, initially at rest, push off from each other. Ricardo weighs more than Paula.

sveta [45]

Answer:

the two ice skater have the same momentum but the are in different directions.

Paula will have a greater speed than Ricardo after the push-off.

Explanation:

Given that:

Two ice skaters, Paula and Ricardo, initially at rest, push off from each other. Ricardo weighs more than Paula.

A. Which skater, if either, has the greater momentum after the push-off? Explain.

The law of conservation of can be applied here in order to determine the skater that possess a greater momentum after the push -off

The law of conservation of momentum states that the total momentum of two or more objects acting upon one another will not change, provided there are no external forces acting on them.

So if two objects in motion collide, their total momentum before the collision will be the same as the total momentum after the collision.

Momentum is the product of mass and velocity.

SO, from the information given:

Let represent the mass of Paula with $m_{Pa}$ and its initial velocity with $u_{Pa}$

Let represent the mass of Ricardo with $m_{Ri}$ and its initial velocity with $u_{Ri}$

At rest ;

their velocities will be zero, i.e

$u_{Pa}$ = $u_{Ri}$ = 0

The initial momentum for this process can be represented as :

$m_{Pa}$ $u_{Pa}$ + $m_{Ri}$ $u_{Ri}$ = 0

after push off from each other then their final velocity will be $v_{Pa}$ and $v_{Ri}$

The we can say their final momentum is:

$m_{Pa}$ $v_{Pa}$ + $m_{Ri}$ $v_{Ri}$ = 0

Using the law of conservation of momentum as states earlier.

Initial momentum = final momentum = 0

$m_{Pa}$ $u_{Pa}$ + $m_{Ri}$ $u_{Ri}$ = $m_{Pa}$ $v_{Pa}$ + $m_{Ri}$ $v_{Ri}$

Since the initial velocities are stating at rest then ; u = 0

$m_{Pa}$ (0) + $m_{Pa}$ (0) = $m_{Pa}$ $v_{Pa}$ + $m_{Ri}$ $v_{Ri}$

$m_{Pa}$ $v_{Pa}$ + $m_{Ri}$ $v_{Ri}$ = 0

$m_{Pa}$ $v_{Pa}$ = - $m_{Ri}$ $v_{Ri}$

Hence, we can conclude that the two ice skater have the same momentum but the are in different directions.

B. Which skater, if either, has the greater speed after the push-off? Explain.

Given that Ricardo weighs more than Paula

So $m_{Ri} > m_{Pa}$ ;

Then $\mathsf{\dfrac{{m_{Ri}}}{m_{Pa} }= 1}$

The magnitude of their momentum which is a product of mass and velocity can now be expressed as:

$m_{Pa}$ $v_{Pa}$ = $m_{Ri}$ $v_{Ri}$

The ratio is

$\dfrac{v_{Pa}}{v_{Ri}} =\dfrac{m_{Ri}}{m_{Pa}} = 1$

$v_{Pa} >v_{Ri}$

Therefore, Paula will have a greater speed than Ricardo after the push-off.

6 0

2 years ago

4. Point B on a wheel of radius 40 cm that is rotating at a constant 5. 0 revolutions

inysia [295]

Answer:

SD

Explanation:

3 0

2 years ago