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3 years ago

Plz help me with #4 it’s 15 points!!

Physics

1 answer:

vovangra [49]3 years ago

3 0

When you push a coin across a Table , the unbalanced force is that force which cause the change in motion of the object.That's why the coin is moving forward.So force applied by my fingers and Frictional force applied by the table on the coin are Unbalanced forces.

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A 160 g basketball has a 32.7 cm diameter and may be approximated as a thin spherical shell. Starting from rest, how long will i

mafiozo [28]

Answer:

t = 0.24 s

Explanation:

As seen in the attached diagram, we are going to use dynamics to resolve the problem, so we will be using the equations for the translation and the rotation dyamics:

Translation: ΣF = ma

Rotation: ΣM = Iα ; where α = angular acceleration

Because the angular acceleration is equal to the linear acceleration divided by the radius, the rotation equation also can be represented like:

ΣM = I(a/R)

Now we are going to resolve and combine these equations.

For translation: Fx - Ffr = ma

We know that Fx = mgSin27°, so we substitute:

(1) mgSin27° - Ffr = ma

For rotation: (Ffr)(R) = (2/3mR²)(a/R)

The radius cancel each other:

(2) Ffr = 2/3 ma

We substitute equation (2) in equation (1):

mgSin27° - 2/3 ma = ma

mgSin27° = ma + 2/3 ma

The mass gets cancelled:

gSin27° = 5/3 a

a = (3/5)(gSin27°)

a = (3/5)(9.8 m/s²(Sin27°))

a = 2.67 m/s²

If we assume that the acceleration is a constant we can use the next equation to find the velocity:

V = √2ad; where d = 0.327m

V = √2(2.67 m/s²)(0.327m)

V = 1.32 m/s

Because V = d/t

t = d/V

t = 0.327m/1.32 m/s

t = 0.24 s

7 0

3 years ago

An inductor with an inductance of 2.30H and a resistance of 8.00 Ω isconnected to the terminals of a battery with an emf of 6.00

Basile [38]

Answer:

(a). The initial rate is 2.60 A/s.

(b). The rate of current increases is 0.8658 A/s.

(c). The current is 0.435 A.

(d). The final steady-state current is 0.75 A.

Explanation:

Given that,

Inductance = 2.30 H

Resistance = 8.00 Ω

Voltage = 6.00 V

(a). We need to calculate the initial rate of increase of current in the circuit.

Using formula of initial rate

$V=initial\ rate\times inductance$

$initial\ rate=\dfrac{V}{L}$

Put the value into the formula

$initial \rate=\dfrac{6.00}{2.30}$

$initial\ rate=2.60\ A/s$

The initial rate is 2.60 A/s.

(b). We need to calculate the rate of increase of current at the instant when the current is 0.500

Using formula of rate of increase of current

$rate\ of \ current\ increase=initial\ rate\times e^{\dfrac{-t}{T}}$ ....(I)

Where, $T=\dfrac{L}{R}$

$T=\dfrac{2.30}{8.00}$

$T=0.2875$

Using formula of current

$i=\dfrac{V}{R}(1-e^{\dfrac{-t}{T}})$

$e^{\dfrac{-t}{T}}=1-(i\times\dfrac{R}{V})$

$e^{\dfrac{-t}{T}}=1-(0.500\times\dfrac{8.00}{6.00})$

$e^{\dfrac{-t}{T}}=0.333$

The rate of current increases is

Put the value in the equation (I)

$rate\ of\ current\ increase=2.60\times0.333$

$rate\ of\ current\ increase=0.8658\ A/s$

The rate of current increases is 0.8658 A/s.

(c). We need to calculate the current

Using formula of current

$i=\dfrac{V}{R}(1-e^{\dfrac{-t}{T}})$

Put the value into the formula

$i=\dfrac{6.00}{8.00}\times(1-e^{\dfrac{-0.250}{0.2875}})$

$i=0.435\ A$

The current is 0.435 A.

(d). We need to calculate the final steady-state current

Using formula of steady state

$i=\dfrac{V}{R}$

$i=\dfrac{6.00}{8.00}$

$i=0.75\ A$

The final steady-state current is 0.75 A.

Hence, This is the required solution.

3 0

3 years ago

What is the chemical name for lime

Sergio039 [100]

Calcium Oxide
CaO I think

5 0

3 years ago

Question 3 of 15

4vir4ik [10]

Answer:

A. Trial and error

Explanation:

Trial and error method is a method adopted when trying to solve a quadratic equation. This equation is mostly the balancing of the right hand side and the left hand side in-order to form a unique point or to equate to zero when one is subtracted from the other. <em>In trail and error method, the coefficients is used to determine when the actual equation is balanced and the likely answer it should be if the equation is expanded through multiplication method.</em>

5 0

3 years ago

What is the electric potential at a distance of 1.2 m from a 7.5 UC point charge?

grandymaker [24]

Answer:

A. 5.6x10^4

Explanation:

Big Brain

7 0

3 years ago

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