Can you help me on this fast just the second one

Tema [17]

The equation for the de Broglie wavelength is:
λ = (h/mv) √[1-(v²/c²)], 
where h is Plank's Constant, m is the rest mass, v is velocity, and c is the velocity of light in vacuum. However, if c>>v (and it is, in this case) then the expression under the radical sign approaches 1, and the equation simplifies to: 
λ = h/mv. 
Substituting, (remember to convert the mass to kg, since 1 J = 1 kg·m²/s²): 
λ = (6.63x10^-34 J·s) / (0.0459 kg) (72.0 m/s) = 2.00x10^-34 m.

8 0

3 years ago

The Doppler effect occurs when a source of sound moves

Dmitrij [34]

The Doppler effect occurs when a source of sound or light
moves either toward or away from the observer.

4 0

3 years ago

What is Newton's third law motion answer part a and b

Olenka [21]

Answer:

hope it helps

Explanation:

Newtons third law is that objects exert equal and opposite forces on each other.

'every action has an equal and opposite reaction'.

3 0

2 years ago

Read 2 more answers

A 500 kg dragster accelerates from rest to a final speed of 100 m/s in 400 m (about a quarter of a mile) and encounters an avera

Fantom [35]

In order to accelerate the dragster at a speed $v_f = 100 m/s$ , its engine must do a work equal to the increase in kinetic energy of the dragster. Since it starts from rest, the initial kinetic energy is zero, so the work done by the engine to accelerate the dragster to 100 m/s is
$W= K_f - K_i = K_f = \frac{1}{2}mv_f^2=2.5 \cdot 10^6 J$

however, we must take into account also the fact that there is a frictional force doing work against the dragster, and the work done by the frictional force is:
$W_f = F_f d = -(1200 N)(400 m)= -4.8 \cdot 10^5 J$
and the sign is negative because the frictional force acts against the direction of motion of the dragster.

This means that the total work done by the dragster engine is equal to the work done to accelerate the dragster plus the energy lost because of the frictional force, which is $-W_f$ :
$W_t = W + (-W_f)=2.5 \cdot 10^6 J+4.8 \cdot 10^5 J=2.98 \cdot 10^6 J$

So, the power delivered by the engine is the total work divided by the time, t=7.30 s:
$P= \frac{W}{t}= \frac{2.98 \cdot 10^6 J}{7.30 s}=4.08 \cdot 10^6 W$

And since 1 horsepower is equal to 746 W, we can rewrite the power as
$P=4.08 \cdot 10^6 W \cdot \frac{1 hp}{746 W} =547 hp$

3 0

3 years ago

Read 2 more answers

An ice rink is 200 feet long and 85 feet wide. The four corners of the rink are rounded to a radius of 24 feet. What is the surf

Nastasia [14]

Answer:

16,506 ft²

Explanation:

There are different ways you can divide the area using rectangles and circles. One way is to find the area of the entire width and length, then subtract the empty areas in the corners.

If we take the empty areas and put them together, we find their area is the area of a square minus the area of a circle.

A = (2r)² − πr²

A = 4r² − πr²

A = (4 − π) r²

So the area of the rink is:

A = WL − (4 − π) r²

A = (85)(200) − (4 − π) (24)²

A ≈ 16,506 ft²

5 0

3 years ago