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All chordates are vertebrates? A. True B. False

makvit [3.9K]

This is true chordates are vertebrae

3 0

4 years ago

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Which statement about covalent bonds is true

g100num [7]

In covalent bonds the atoms share electrons.

7 0

3 years ago

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Suppose your salary in 2012 is $70,000. Assuming an annual inflation rate of 7%, what salary do you need to earn in 2020 in orde

s2008m [1.1K]

Annual salary(2012) = $70,000

Annual inflation = 7%

Therefore, the salary you need to earn in 2020 in order to have the same purchasing power can be calculated below

$2020-2012=8\text{ years}$ $FV=PV\times(1+r)^n$

where

n = 8

r = 7/100 = 0.07

PV = 70, 000

$\begin{gathered} FV=70,000(1+0.07)^8 \\ FV=70000(1.07)^8 \\ FV\text{ = 70000}\times1.71818617983 \\ FV=120273.032588 \\ FV=\text{ \$}120,273.03 \end{gathered}$

The salary you need to earn in 2020 to have the same purchasing power = $120, 273.03

8 0

1 year ago

A 20-cm long solenoid consists of 100 turns of a coil of radius r = 3.0 cm. A current of Io in the coiled wire produces a magnet

Romashka-Z-Leto [24]

Answer:

vi) Double the current in the wire, and double the number of turns in the 20-cm long solenoid

Explanation:

The magnetic field inside the solenoid and the current flowing in the coil of solenoid are related to each other by the following equation

B₀=μ₀nI₀

Where,

B₀ is the magnetic field in the middle of solenoid

n is the number of turns in the coil of solenoid

I₀ is the current flowing in the coil of solenoid

In the above equation, as μ₀ is a constant so the magnetic field will be directly proportional to the number of turns multiplied by the current. So, changing the radius of the coil or length of the coil will have no effect on the magnetic field.

As we have to increase the magnetic field by 4 times, we need to double the current as well as the number of turns as mentioned in the option vi.

3 0

4 years ago

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In an elastic collision, a 400-kg bumper car collides directly from behind with a second, identical bumper car that is traveling

kirza4 [7]

Answer:

v₁ = 3.5 m/s

v₂ = 6.4 m/s

Explanation:

We have the following data:

m₁ = mass of trailing car = 400 kg

m₂ = mass of leading car = 400 kg

u₁ = initial speed of trailing car = 6.4 m/s

u₂ = initial speed of leading car = 3.5 m/s

v₁ = final speed of trailing car = ?

v₂ = final speed of leading car = ?

The final speed of the leading car is given by the following formula:

$v_2=\frac{2m_1}{m_1+m_2}u_1-\frac{m_1-m_2}{m_1+m_2}u_2\\\\v_2=\frac{(2)(400\ kg)}{400\ kg+400\ kg}(6.4\ m/s)-\frac{400\ kg-400\ kg}{400\ kg + 400\ kg}(3.5\ m/s)$

v₂ = 6.4 m/s

The final speed of the leading car is given by the following formula:

$v_1=\frac{m_1-m_2}{m_1+m_2}u_1+\frac{2m_2}{m_1+m_2}u_2\\\\v_1=\frac{400\ kg-400\ kg}{400\ kg + 400\ kg}(6.4\ m/s)+\frac{(2)(400\ kg)}{400\ kg+400\ kg}(3.5\ m/s)$

v₁ = 3.5 m/s

4 0

3 years ago