Ask question

Ask question

All categories

2 years ago

6

A driver drove for 3 hours at a certain speed. if he drove 12 more miles at the same speed, the distance would be 132 miles. at

what speed did he drive?

1 answer:

Zepler [3.9K]2 years ago

4 0

Answer:

40mph

Explanation:

1st leg DATA:

time = 3 hrs ; speed = r mph ; distance = 3r miles

------------

2nd leg DATA:

speed = r mph ; distance = 12 miles

--------------------------------

3r + 12 = 132

3r = 120

rate = 40 mph

You might be interested in

Two lightbulbs work on a 120-V circuit One 50 W and the other is 100 W. Which bulb has a higher resistance? Explain pls!!!!

Sladkaya [172]

Answer:

Bulb 1 has more resistance.

Explanation:

Given that,

Two lightbulbs work on a 120-V circuit.

The power of circuit 1, P₁ = 50 W

The power of circuit 2, P₂ = 100 W

We need to find the bulb that has a higher resistance.

The power of the bulb is given by :

$P = \dfrac{V^2}{R}$

For bulb 1,

$R_1=\dfrac{V^2}{P_1}\\\\R_1=\dfrac{(120)^2}{50}\\\\R_1=288\ \Omega$

For bulb 2,

$R_2=\dfrac{V^2}{P_2}\\\\R_2=\dfrac{(120)^2}{100}\\\\R_2=144\ \Omega$

So, bulb 1 has higher resistance.

8 0

2 years ago

If a compound forms by ionic bonding, which is not true?

MrRa [10]

Answer:is deez nut;D

Explanation:

because u gay...

5 0

3 years ago

Read 2 more answers

Guys please help me out I’ll give extra points

zvonat [6]

Answer: h = 3.34 m

Explanation:

If the hat is thrown straight up, then at its highest point it has no motion and no kinetic energy. All energy is potential energy

PE = mgh

h = PE/mg = 4.92 / (0.150(9.81)) = 3.34352... ≈3.34 m

8 0

3 years ago

What is the velocity of a car that travels -50 meters in 5 seconds then 10 meters in 5 seconds

diamong [38]

Answer:

2 m/s

Explanation:

The first part of the question the car is going in reverse or negative along the x axis. Then the second part the car is moving forward along the x axis. So the car would only have velocity in the current direction of movement. So our equation for velocity is as follows.

v = d/t

v = 10 m/5 s

v = 2 m/s

3 0

2 years ago

Two students are on a balcony 19.1 m above the street. One student throws a ball, b1, vertically downward at 13.9 m/s. At the sa

tester [92]

Answer:

Part a)

$t = 2.83 s$

Part b)

Ball thrown downwards = $v_f = 23.8 m/s$

Ball thrown upwards = $v_f = 23.8 m/s$

Part c)

$d = 22.24 m$

Explanation:

Part a)

Since both the balls are projected with same speed in opposite directions

So here the time difference is the time for which the ball projected upward will move up and come back at the same point of projection

Afterwards the motion will be same as the first ball which is projected downwards

so here the time difference is given as

$\Delta y = 0 = v_y t + \frac{1}{2}at^2$

$0 = 13.9 t - \frac{1}{2}(9.81) t^2$

$t = 2.83 s$

Part b)

Since the displacement in y direction for two balls is same as well as the the initial speed is also same so final speed is also same for both the balls

so it is given as

$v_f^2 - v_i^2 = 2 a \Delta y$

$v_f^2 - (13.9)^2 = (2)(-9.81)(-19.1)$

$v_f^2 = 567.9$

$v_f = 23.8 m/s$

Part c)

Relative speed of two balls is given as

$v_{12} = v_1 - v_2$

$v_{12} = (13.9) - (-13.9) = 27.8 m/s$

now the distance between two balls in 0.8 s is given as

$d = v_{12} t$

$d = 27.8 \times 0.8$

$d = 22.24 m$

7 0

3 years ago