Which optical device can focus light to a point through reflection?

One component of a metal sculpture consists of a solid cube with an edge of length 38.9 cm. The alloy used to make the cube has

vovangra [49]

Answer:

The mass of the cube is 420.8 kg.

Explanation:

Given that,

Length of edge = 38.9 cm

Density $\rho= 7.15 \times10^{3}\ kg/m^3$

We need to calculate the volume of cube

Using formula of volume

$V = 38.9^3$

$V=0.058863\ m^3$

We need to calculate the mass of the cube

Using formula of density

$\rho = \dfrac{m}{V}$

$m = V\times\rho$

$m =0.058863\times7.15 \times10^{3}$

$m=420.8\ kg$

Hence, The mass of the cube is 420.8 kg.

7 0

1 year ago

A balloon drifts 140m toward the west in 45s ; then the wind suddenly changes and the balloon flies 90m toward the east in the n

Bogdan [553]

Answer: 140 m

Explanation:

Let's begin by stating clear that motiont is the change of position of a body at a certain time. So, during this motion, the balloon will have a trajectory and a displacement, being both different:

The trajectory is the path followed by the body, the distance it travelled (is a scalar quantity).

The displacement is the distance in a straight line between the initial and final position (is a vector quantity).

So, according to this, the distance the balloon traveled during the first 45 s (its trajectory) is 140 m.

But, if we talk about displacement, we have to draw a straight line between the initial position of the balloon (point 0) to its final position (point 90 m). Being its displacement 95 m.

8 0

1 year ago

A boy and a girl are riding a merry-go-round which is turning at a constant rate. the boy is near the outer edge, while the girl

scZoUnD [109]

I think that the girl has greater tangential acceleration because she is closer to the center and the acceleration is greater there.

7 0

2 years ago

Read 2 more answers

If the frequencies of two component waves are 24 Hz and 20 Hz, they should produce _______ beats per second.

horrorfan [7]

This can be answered using the beat frequency formula, which is simply the difference between 2 frequencies.

Let: fᵇ = beat frequency
f₁ = first frequency
f₂ = second frequency

fᵇ = |f₁ - f₂|

substituting the values:
fᵇ = |24Hz - 20Hz|
fᵇ = 4Hz

The unit Hz also means beats per second, therefore:
fᵇ = 4 beats per second

Therefore, the answer is C. 4

8 0

2 years ago

Read 2 more answers

A nonuniform, 80.0-g, meterstick balances when the support is placed at the 51.0-cm mark. At what location on the meterstick sho

Gnoma [55]

Answer:34 cm

Explanation:

Given

mass of meter stick m=80 gm

stick is balanced when support is placed at 51 cm mark

Let us take 5 gm tack is placed at x cm on meter stick so that balancing occurs at x=50 cm mark

balancing torque