1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
kompoz [17]
3 years ago
6

Lindsey started biking to the park traveling 15 mph, after some time the bike got a flat so Lindsey walked the rest of the way,

traveling 4 mph. If the total trip to the park took 5 hours and it was 53 miles away, how long did Lindsey travel at each speed
Physics
1 answer:
-BARSIC- [3]3 years ago
5 0

Answer:

Lindsey biked 45 miles for 3 hours at 15 mph and walked 8 miles for 2 hours at 4 mph.

Explanation:

Speed = distance/time

Let the distance that Lindsey biked through be x miles and the time it took her to bike through that distance be t hours

Then, the rest of the distance that she walked is (53 - x) miles

And the time she spent walking that distance = (5 - t) hours

Her biking speed = 15 mph = 15 miles/hour

Speed = distance/time

15 = x/t

x = 15 t (eqn 1)

Her walking speed = 4 mph = 4 miles/hour

4 = (53 - x)/(5 - t)

53 - x = 4 (5 - t)

53 - x = 20 - 4t (eqn 2)

Substitute for X in (eqn 2)

53 - 15t = 20 - 4t

15t - 4t = 53 - 20

11t = 33

t = 3 hours

x = 15t = 15 × 3 = 45 miles.

(53 - x) = 53 - 45 = 8 miles

(5 - t) = 5 - 3 = 2 hours

So, it becomes evident that Lindsey biked 45 miles for 3 hours at 15 mph and walked 8 miles for 2 hours at 4 mph.

You might be interested in
If a trapezoidal channel has side slopes of 1:1, hydraulic depth is 5 feet, the bottom width is 8 feet, flow is 2,312 cubic feet
Evgesh-ka [11]

Answer:

S = \dfrac{1}{2.5}

Explanation:

given,

side slope = 1 : 1

hydraulic depth(y) = 5 ft

bottom width (b)= 8 ft

x = 1

Q = 2,312 ft³/s

n = 0.013

slope of channel = ?

R = \dfrac{A}{P}

R = \dfrac{y(b + xy)}{b+2y\sqrt{1+x^2}}

R = \dfrac{5(8+ 5)}{8+2\times 5\sqrt{1+1^2}}

R = 4.69 m

using manning's equation

Q = \dfrac{1}{n}AR^{2/3} S^{1/2}

2312= \dfrac{1}{0.013}\times (5(8+5))\times 4.69^{2/3} S^{1/2}

2312=14009.37\times S^{1/2}

S = 0.406

S = \dfrac{1}{2.5}

5 0
3 years ago
72.0-kg person pushes on a small doorknob with a force of 5.00 N perpendicular to the surface of the door. The doorknob is locat
expeople1 [14]

Answer:I=2 kg-m^2

Explanation:

Given

mass m=72 kg

Force F=5 N

door knob is located at a distance of r=0.8 m from axis

Angular acceleration of door \alpha =2 rad/s^2

Torque T=I\alpha =F\times r

where I=moment of inertia

5\times 0.8=I\times 2

I=2 kg-m^2

4 0
4 years ago
Suppose an event is measured to be at a = (0,-2, 3, 5) in one reference frame. Find the components of this event in another refe
LenaWriter [7]

Answer:

The components of the moving frame is (8.07c, -2, 3, 9.493)

Solution:

As per the question:

Velocity of moving frame w.r.t original frame v_{m} 0.85c

Point 'a' of an event in one reference frame corresponds to the (x, y, z, t) coordinates of the plane

a = (0, - 2, 3, 5)

Now, according the the question, the coordinates of moving frame, say (X, Y, Z, t'):

New coordinates are given by:

X = \frac{x - v_{m}t}{\sqrt{1 - \frac{v_{m}^{2}}{c^{2}}}}

X = \frac{0 - 0.85c\times 5}{\sqrt{1 - \frac{(0.85c)^{2}}{c^{2}}}}

X = 8.07 c

Now,

Y = y = - 2

Z = z = 3

Now,

t' = \frac{t - \frac{vx}{c}^{2}}{\sqrt{1 - (\frac{v}{c})^{2}}}

t' = \frac{5 - 0}{\sqrt{1 - (\frac{0.85c}{c})^{2}}} = 9.493 s

4 0
3 years ago
How to not get heart attacks ? And what is some plans/list for a healthy diet ?
Mamont248 [21]

Answer:

hey there

( i )we have to Choose good nutrition. A healthy diet is one of the best weapons you have to fight cardiovascular disease. and should be physically active and stop smoking if you do these are some

life style changes though which can prevent heart attacks

( ii )An healthy diet for heart

lots of fruits and vegetables.

nuts, beans, and legumes.

whole grains.

plant-based oils, such as olive oil.

low-fat dairy products.

Explanation:

Hope it helps you

have a nice day :)

6 0
3 years ago
True or False: The arrows on a motion map should point in the directions of motion.
slavikrds [6]

Answer:

true,true,false

Explanation:

its false because if it is equal it would show an arrow pointing left and a 20 and the same for the right

3 0
3 years ago
Other questions:
  • When you push on an object such as a wrench, a steel pry bar, or even the outer edge of a door, you produce a torque equal to th
    10·1 answer
  • Two astronauts are 1.5m apart in their spaceship.One speaks to the other. The conversation is transmitted to earth via electroma
    13·1 answer
  • A horizontal desk surface measures 1.7 m by 1.0 m. If the Earth's magnetic field has magnitude 0.42 mT and is directed 68° below
    14·1 answer
  • If we want to describe work we must have
    8·1 answer
  • A jet airplane flying from Darwin, Australia, has an air speed of 260 m/s in a direction 5.0º south of west. It is in the jet st
    13·1 answer
  • Communicable diseases can be prevented by:
    14·1 answer
  • Look at the two vectors below:
    7·1 answer
  • Does gravity exist between a pencil on a coffee mug
    11·1 answer
  • How does weathering produce soil
    7·1 answer
  • If an object moves with constant acceleration, its velocity must
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!