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3 years ago

Please help me with this question guys.

Physics

1 answer:

katen-ka-za [31]3 years ago

7 0

Answer:

<em>The average speed is 22.2 km/h</em>

Explanation:

<u>Average Speed</u>

Given an object travels a total distance d and took a total time t, then the average speed is:

$\displaystyle \bar v=\frac{d}{t}$

The mailman first drives d1=7 km at v1=15 km/h. The time taken to drive is:

$\displaystyle t1=\frac{d1}{v1}=\frac{7}{15}=0.467\ h$

Then he drives d2=7 km at v2=43 km/h taking a time of:

$\displaystyle t2=\frac{d2}{v2}=\frac{7}{43}=0.163\ h$

The total time is

t=0.467 h + 0.163 h = 0.63 h

The total distance is

d = 7 km + 7 km = 14 km

The average speed is:

$\displaystyle \bar v=\frac{14}{0.63}=22.2\ km/h$

The average speed is 22.2 km/h

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Afina-wow [57]

Answer:

2.76×10⁻¹⁰ C

Explanation:

Applying,

V = W/q................... Equation 1

Where V = Electric Potential, E = Electric potential energy, q = charge.

make q the subject of the equation

q = W/V................ Equation 2

From the question,

Given: W = 4.26×10⁻⁸ J, V = 154.5 V

Substitute these values into equation 2

q = 4.26×10⁻⁸/154.5

q = 2.76×10⁻¹⁰ C

3 0

3 years ago

A shell is shot with an initial velocity v with arrow0 of 18 m/s, at an angle of θ0 = 60° with the horizontal. At the top of the

BARSIC [14]

Answer:

D = 43 m

Explanation:

given,

initial velocity = 18 m/s

angle θ = 60°

total horizontal distance covered by the shell is

$R = \dfrac{v_0^2sin 2\theta}{g}$

applying conservation of momentum in horizontal direction

m v₀ cos θ = m₁v₁ + m₂ v₂

m v₀ cos θ = 0.5 m v₂

v₂ = 2 v₀ cos θ.

distance covered by the shell from point of explosion

R' = v t

= $(2 v_0 cos \theta) (\dfrac{v_0^2sin \theta}{g})$

= $(2 \dfrac{v_0^2cos \theta sin \theta}{g})$

= $\dfrac{v_0^2sin 2\theta}{g}$

= R

total distance traveled by the shell is

D = $\dfrac{R}{2}+R'$

= 1.5 R

= $1.5\dfrac{v_0^2sin 2\theta}{g}$

D = $1.5\dfrac{18^2sin 2\times 60}{9.81}$

= 42.9 ≅ 43 m

D = 43 m

3 0

3 years ago

The reaction energy of a reaction is the amount of energy released by the reaction. It is found by determining the difference in

solmaris [256]

Answer: the correct answer is 7.8026035971 x 10^(-13) joule

Explanation:

Use Energy Conservation. By ``alpha decay converts'', we mean that the parent particle turns into an alpha particle and daughter particles. Adding the mass of the alpha and daughter radon, we get

m = 4.00260 u + 222.01757 u = 226.02017 u .

The parent had a mass of 226.02540 u, so clearly some mass has gone somewhere. The amount of the missing mass is

Delta m = 226.02540 u - 226.02017 u = 0.00523 u ,

which is equivalent to an energy change of

Delta E = (0.00523 u)*(931.5MeV/1u)

Delta E = 4.87 MeV

Converting 4.87 MeV to Joules

1 joule [J] = 6241506363094 mega-electrón voltio [MeV]

4 mega-electrón voltio = 6.40870932 x 10^(-13) joule

4.87 mega-electrón voltio = 7.8026035971 x 10^(-13) joule

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4 years ago

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Answer:

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3 years ago

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Answer:

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4 years ago

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