A car headed north at 15.0 m/s experiences an acceleration of 2.50 m/s2 for 3.00 s. What is the final velocity of the car?

The charge entering the positive terminal of an element is q = 5 sin 4πt mC while the voltage across the element (plus to minus)

Artemon [7]

Answer:

(a). The power delivered to the element is 187.68 mW

(b). The energy delivered to the element is 57.52 mJ.

Explanation:

Given that,

Charge $q=5\sin4\pi t\ mC$

Voltage $v=3\cos4\pi t\ V$

Time t = 0.3 sec

We need to calculate the current

Using formula of current

$i(t)=\dfrac{dq}{dt}$

Put the value of charge

$i(t)=\dfrac{d}{dt}(5\sin4\pi t)$

$i(t)=5\times4\pi\cos4\pi t$

$i(t)=20\pi\cos4\pi t$

(a).We need to calculate the power delivered to the element

Using formula of power

$p(t)=v(t)\times i(t)$

Put the value into the formula

$p(t)=3\cos4\pi t\times20\pi\cos4\pi t$

$p(t)=60\pi\times10^{-3}\cos^2(4\pi t)$

$p(t)=60\pi\times10^{-3}(\dfrac{1+\cos8\pi t}{2})$

Put the value of t

$p(t)=60\pi\times10^{-3}(\dfrac{1+\cos8\pi\times0.3}{2})$

$p(t)=30\pi\times10^{-3}(1+\cos8\pi \times0.3)$

$p(t)=187.68\ mW$

(b). We need to calculate the energy delivered to the element between 0 and 0.6 s

Using formula of energy

$E(t)=\int_{0}^{t}{p(t)dt}$

Put the value into the formula

$E(t)=\int_{0}^{0.6}{30\pi\times10^{-3}(1+\cos8\pi \times t)}$

$E(t)=30\pi\times10^{-3}\int_{0}^{0.6}{1+\cos8\pi \times t}$

$E(t)=30\pi\times10^{-3}(t+\dfrac{\sin8\pi t}{8\pi})_{0}^{0.6}$

$E(t)=30\pi\times10^{-3}(0.6+\dfrac{\sin8\pi\times0.6}{8\pi}-0-0)$

$E(t)=57.52\ mJ$

Hence, (a). The power delivered to the element is 187.68 mW

(b). The energy delivered to the element is 57.52 mJ.

6 0

3 years ago

What do you know about muscular fitness activities?

Ulleksa [173]

Answer:

Examples of muscle-strengthening activities include:

lifting weights.

working with resistance bands.

heavy gardening, such as digging and shovelling.

climbing stairs.

hill walking.

cycling.

dance.

push-ups, sit-ups and squats.

Explanation:

3 0

3 years ago

Covalent Bonds usually bond atoms of which type of elements together?

anzhelika [568]

<h2>Answer: Nonmetals to Nonmetals </h2>

Covalent bonds hold non-metallic atoms together. These atoms have many electrons in their outermost level and have a tendency to gain electrons rather than to yield them.

In this case the bond is formed by sharing a pair of electrons between the two atoms, one from each atom. Then, this pair of shared electrons is common to the two atoms and holds them together, so that both atoms acquire more stability.

Therefore the correct answer is C.

5 0

4 years ago

What is the energy of a baby who weighs 20 N sitting on a 1.5 m high chair

guajiro [1.7K]

The energy of the baby is gravitational potential energy, and it is equal to the weight of the baby times its height from the ground:
$U=(mg) h$
where
mg=20 N is the weight (the mass times the gravitational acceleration)
h=1.5 m is the height from the ground
If we plug the numbers into the equation, we find
$U=(mg)h=(20 N)(1.5 m)=30 J$

3 0

4 years ago

Explaining how caring capacity influences the number of organisms.

Gelneren [198K]

An ecosystem can only sustain so many organisms. That limit would be its <span>carrying capacity. If the population goes above that number then other factors will cause the population to crash and then rebound to a constant level. </span>

5 0

4 years ago