Ask question

Ask question

All categories

3 years ago

10

Juans mother drives 7.25 miles southwest to her favorite shopping mall. What is the average velocity of her automobile if she ar

rives at the mark in 20min?

1 answer:

Irina-Kira [14]3 years ago

5 0

21.75 Miles Per Hour

I got this by multiplying 7.25(3) because I know 20 minutes is 1/3 of 1 he

You might be interested in

The temperature of a sample of water increases from 20°c to 46.6°c as it absorbs 5650 calories of heat what is the mass of the s

kompoz [17]

M=energy transferred/ (temperature change*specific heat) M= 5650/(26.6*1.0) M=212g

4 0

3 years ago

Two forces,one of 12 N and another of 24 N,act on a body in such a way that they make an angle of 90degree with each other.Find

jok3333 [9.3K]

Answer:

26.83 N.

Explanation:

If the angle between two vector is 90°, to get the resultant, we use Pythagoras theorem.

a² = b²+c²......................... Equation 1

Where a = R = Resultant, b = 12 N, c = 24 N.

Substitute these values into equation 1

R² = 12²+24²

R² = 144+576

R² = 720

√R² = √720

R = 26.83 N.

Hence, the result of the two force is 26.83 N.

4 0

2 years ago

A cheetah can run at approximately 100 km/hr and a gazelle at 80 km/hr. If both animals are running at full speed, with a gazell

zimovet [89]

The cheetah's speed is 100x and The gazelle's speed is 80x + 70. Set the two equations equal to each other: 100x = 80x +70 (then subtract 80x from both sides). 20x = 70 (then divide by 20). X =3.5. The cheetah catches the gazelle after 3.5

6 0

3 years ago

An extension cord is used with an electric weed trimmer that has a resistance of 17.9 Ω. The extension cord is made of copper (r

Naddika [18.5K]

Answer:

(a) $R_{c}=0.87ohms$

(b) $V_{T}=114.44V$

Explanation:

Part (a)

The total length of copper cord L=86.3 m

The cross sectional area A=1.71×10⁻⁶m²

The resistivity of copper p=1.72×10⁻⁸Ω

Thus the resistance of extension cord is

$R_{c}=p\frac{L}{A}\\R_{c}=(1.72*10^{-8} )\frac{86.3}{1.71*10^{-6}}\\R_{c}=0.87ohms$

Part (b)

The resistance of trimmer Rt=17.9 ohms

When voltage of 120V is applied then the current I is passing through series circuit is

$I=\frac{120V}{R_{c} +R_{T} }\\I=\frac{120V}{0.87 +17.9 } \\I=6.4A$

Thus the voltage across the trimmer is:

$V_{T}=IR_{T}\\V_{T}=(6.4)*(17.9)\\V_{T}=114.44V$

8 0

3 years ago

A football player kicks a football downfield. The height of the football increases until it reaches a maximum height of 15 yards

Trava [24]

Answer:

kick 1 has travelled 15 + 15 = 30 yards before hitting the ground

so kick 2 travels 25 + 25 = 50 yards before hitting the ground

first kick reached 8 yards and 2nd kick reached 20 yards

Explanation:

1st kick travelled 15 yards to reach maximum height of 8 yards

so, it has travelled 15 + 15 = 30 yards before hitting the ground

2nd kick is given by the equation

y (x) = -0.032x(x - 50)

$Y = 1.6 X - 0.032x^2$

we know that maximum height occurs is given as

$x = -\frac{b}{2a}$

$y =- \frac{1.6}{2(-0.032)} = 25$

and maximum height is

$y = 1.6\times 25 - 0.032\times 25^2$

y = 20

so kick 2 travels 25 + 25 = 50 yards before hitting the ground

first kick reached 8 yards and 2nd kick reached 20 yards

8 0

3 years ago

Read 2 more answers