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3 years ago

I dont know how to do question 3，4

Physics

1 answer:

dlinn [17]3 years ago

7 0

<span>Prior to the Cambrian, organisms with hard parts (eg. shells and bones) weren't present for most the time, and it's generally such hard parts that get to fossilize. There's also been more time for Precambrian deposits to get destroyed by natural processes, </span>

<span>The supply of Precambrian fossils has actually greatly improved over the last few decades. The so called Ediacaran faunas have been found at many parts of the world, and would be worth looking into.hope it helps</span>

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On what factors capacitance of parallel plate capacitor depends?

Roman55 [17]

Answer:

Separation between the plates, area of the plates and dielectric constant

Explanation:

The capacitance of a parallel plate capacitor is given by:

$C=k \epsilon_0 \frac{A}{d}$

where

k is the dielectric constant

$\epsilon_0$ is the vacuum permittivity (which has a constant value)

A is the area of the plates

d is the separation between the plates

Therefore from the formula we see that the capacitance of a parallel plate capacitor depends on the following factors:

- Separation between the plates

- Area of the plates

- Dielectric constant

3 0

2 years ago

12. A flat circular coil of wire having 200 turns and diameter 6.0 cm carries a current of 7.0 A. It is placed in a magnetic fie

IgorLugansk [536]

Answer:

The magnitude of the magnetic torque on the coil is 1.98 A.m²

Explanation:

Magnitude of magnetic torque in a flat circular coil is given as;

τ = NIASinθ

where;

N is the number of turns of the coil

I is the current in the coil

A is the area of the coil

θ is the angle of inclination of the coil and magnetic field

Given'

Number of turns, N = 200

Current, I = 7.0 A

Angle of inclination, θ = 30°

Diameter, d = 6 cm = 0.06 m

A = πd²/4 = π(0.06)²/4 = 0.002828 m²

τ = NIASinθ

τ = 200 x 7 x 0.002828 x Sin30

τ = 1.98 A.m²

Therefore, the magnitude of the magnetic torque on the coil is 1.98 A.m²

4 0

3 years ago

A bullet of mass 6.20 10-3 kg, moving at 1320 m/s impacts a tree stump and penetrates 11.00 cm into the wood before coming to re

sladkih [1.3K]

Answer:

F = -49.1 10³ N

Explanation:

Let's use the kinematics to find the acceleration the acceleration of the bullet that they tell us is constant

$v_{f}$ ² = v₀² + 2 a x

Since the bullet is at rest, the final speed is zero

x = 11.00 cm (1 m / 100 cm) = 0.110 m

0 = v₀² + 2 a x

a = -v₀² / 2 x

a = -1320²/(2 0.110)

a = -7.92 10⁶ m / s²

With Newton's second law we find the force

F = m a

F = 6.20 10⁻³ (-7.92 10⁶)

F = -49.1 10³ N

The sign means that it is the force that the tree exerts to stop the bullet

8 0

2 years ago

2. Without changing the mass or height, what else do you think you could do to design a system in which GPE and KE values are mo

Andru [333]

Answer:

jgvvjlvcgkgc

Explanation:

5 0

2 years ago

Two iron bolts of equal Mass one at a hundred see another at 55 Sierra place in the insulated cylinder assuming the heat capacit

malfutka [58]

Answer:

$T_2 = 77.5c$

Explanation:

From the question we are told that

Temp of first bolts $T_1=100$

Temp of 2nd bolt $T_2=55$

Generally the equation showing the relationship between heat & temperature is given by

$q=cm \triangle T$

Generally heat released by the iron bolt = heat gained by the iron bolt

Generally solving mathematically

$-(0.45*m* (T_2-100 \textdegree c)) = 0.45*m*(T_2 -55\textdegree c)$

$-(T_2-100 \textdegree c)) = (T_2 -55 \textdegree c)$

$T_2 +T_2= 100 \textdegree c+55 \textdegree c$

$T_2=\frac{155 \textdegree c}{2}$

$T_2 = 77.5 \textdegree c$

Therefore $T_2 = 77.5 \textdegree c$ is the final temperature inside the container

5 0

2 years ago