All categories

3 years ago

What are the characteristics of an index fossil?

2 answers:

4 0

I think as a mold. when the Flood came in Genesis, i believe that when the fish were washed away, the kinda made a mold in a rock.

Assoli18 [71]3 years ago

4 0

D. Preserved as mold

You might be interested in

High-speed stroboscopic photographs show that the head of a -g golf club is traveling at m/s just before it strikes a -g golf ba

pav-90 [236]

The question is incomplete. The complete question is :

High-speed stroboscopic photographs show that the head of a 200 g golf club is traveling at 60 m/s just before it strikes a 50 g golf ball at rest on a tee. After the collision, the club head travels (in the same direction) at 40 m/s. Find the speed of the golf ball just after impact.

Solution :

We know that momentum = mass x velocity

The momentum of the golf club before impact = 0.200 x 60

= 12 kg m/s

The momentum of the ball before impact is zero. So the total momentum before he impact is 12 kg m/s. Therefore, due to the conservation of momentum of the two bodies after the impact is 12 kg m/s.

Now the momentum of the club after the impact is = 0.2 x 40

= 8 kg m/s

Therefore the momentum of the ball is = 12 - 8

= 4 kg m/s

We know momentum of the ball, p = mass x velocity

4 = 0.050 x velocity

∴ Velocity = $\frac{4}{0.050}$

= 80 m/s

Hence the speed of the golf ball after the impact is 80 m/s.

6 0

3 years ago

The speedometer in a car does not measure the cars velocity because the velocity is a...

OLEGan [10]

...because velocity is a vector quantity, which means that it includes both the magnitude and the direction of motion.

The speedometer only measures the speed of the car and not its velocity. Speed is a scalar quantity, which means that it only indicates magnitude and not direction of the motion. Thus, the speedometer only shows the distance covered by the car with time (speed), but it does not indicate if the car is moving forward, backward, left or right.

7 0

4 years ago

A sound wave of length 45 um travels with a speed of 1800 m/s in a metallic medium. Find the frequency of the sound wave.

Lapatulllka [165]

Hi there!

We can use the following equation:

$\large\boxed{v = \lambda f}$

v = velocity of wave (m/s)
λ = wavelength (μm)

f = frequency (Hz)

We can rearrange the equation to solve for frequency:
$\large\boxed{f = \frac{v}{\lambda}}$

Plug in the givens. Make sure to convert μm to m:

1 μm = 0.000001 m

$f = \frac{1800}{0.000045} = 40000000 Hz = \boxed{40 \cdot 10^6 Hz}$

5 0

2 years ago

A projectile proton with a speed of 1100 m/s collides elastically with a target proton initially at rest. The two protons then m

scoundrel [369]

Answer:

So, the target proton's speed is 777.82 m/s

And, the projectile proton's speed is 777.82 m/s

Explanation:

as per the system, it conserves the linear momentum,

so along x axis :

Mp V1 (i) = Mp V1 (f) cos θ1 + Mp V2 (f) cos θ2

along y axis :

0 = -Mp V1 (f) sin θ1 + Mp V2 (f) sin θ2

let us assume before collision it was moving on positive x axis, hence target angle will be θ2 = 45° from x axis

V2(f) = V1 (i) sin θ1 / ( cosθ2 sin θ1 + cos θ1 sin θ2)

= 1100 * sin 45 / ( cos 45 sin 45 + cos 45 sin 45 )

= 1100 * 0.7071 /( 0.7071 * 0.7071 +0 .7071 * 0.7071 )

= 777.82 /( 0.5 + 0.5)

= 777.82 m/s

(b)

the speed of projectile , V1 (f) = sinθ2 * V2(f) / sinθ1

= sin 45 * 777.82 / sin 45

= 777.82 m/s

So, the target proton's speed is 777.82 m/s

And, the projectile proton's speed is 777.82 m/s

8 0

3 years ago

Can electromagnetic waves be reflected

SashulF [63]

Answer:

Some types of electromagnetic waves, like radio waves, microwaves, infrared waves, visible light and ultraviolet waves, can be reflectedSome types of electromagnetic waves, like radio waves, microwaves, infrared waves, visible light and ultraviolet waves, can be reflected

Explanation:

7 0

3 years ago