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
sammy [17]
3 years ago
14

A truck covered 2/7 of a journey at an average speed of 40

Physics
1 answer:
sertanlavr [38]3 years ago
6 0

Answer:

The amount of time for the whole journey is 8 hours.

Explanation:

A truck covered 2/7 of a journey at an average speed of 40  mph. Representing 1 the total of the trip traveled, then the rest of the distance traveled is calculated as: 1-\frac{2}{7} =\frac{5}{7}

So if the truck covered the remaining 200 miles at \frac{2}{7}, this means that \frac{5}{7} of the trip represents the 200 miles. So, to calculate the total distance traveled by the truck, you apply the following rule of three: if \frac{5}{7} of the route represents 200 miles, the integer 1 (which represents the total of the route), how many miles are they?

miles=\frac{1*200miles}{\frac{5}{7} } =\frac{7}{5} *200 miles

miles= 280

So the total distance traveled is 280 miles. Since speed is the relationship between the space traveled by an object and the time used for it (speed=\frac{distance}{time}), then if the average of the entire trip was 35 mph and the distance traveled 280 miles, the time is calculated as:

time=\frac{distance}{speed}=\frac{280 miles}{35 mph}

time= 8 h

<u><em> The amount of time for the whole journey is 8 hours.</em></u>

<u><em /></u>

You might be interested in
Car A hits car B (initially at rest and of equal mass) frombehind while going 35 m/s. Immediately after the collision, car Bmove
kolezko [41]

Answer:

The fraction of kinetic energy lost in the collision in term of the initial energy is 0.49.

Explanation:

As the final and initial velocities are known it is possible then the kinetic energy is possible to calculate for each instant.

By definition, the kinetic energy is:

k = 0.5*mV^2

Expressing the initial and final kinetic energy for cars A and B:

ki=0.5*maVa_{i}^2+0.5*mbVb_{i}^2

kf=0.5*maVa_{f}^2+0.5*mbVb_{f}^2

Since the masses are equals:

m=ma=mb

For the known velocities, the kinetics energies result:

ki=0.5*mVa_{i}^2

ki=0.5*m(35 m/s)^2=612.5m^2/s^2*m

kf=0.5*mbVb_{f}^2

kf=0.5*m(25 m/s)^2=312.5m^2/s^2*m

The lost energy in the collision is the difference between the initial and final kinectic energies:

kl=ki-kf

kl = 612.5m^2/s^2*m-312.5 m^2/s^2*m=300 m^2/s^2*m

Finally the relation between the lost and the initial kinetic energy:

kl/ki = 300 m^2/s^2 * m / 612.5 m^2/s^2 * m

kl/ki = 24/49=0.49

7 0
3 years ago
A ball is thrown upward. As it passes 5.0 m height it is traveling at 4.0 m/s up. What was its initial upward velocity? (a) 7.0
sveticcg [70]

Answer:

c) 10.7m/s

Explanation:

From the exercise we know that at 5m the ball  is traveling at 4m/s

To calculate its initial velocity we need to solve the following equation:

v_{y}^{2}=v_{oy}^{2}+2g(y-y_{o})

Since the initial height is 0

Solving for v_{o}

v_{oy}=\sqrt{v_{y}^{2}-2gy}=\sqrt{(4m/s)^2-2(-9.8m/s^2)(5m)}=10.7m/s

5 0
3 years ago
If the photon scatters in the backward direction, what is the magnitude of the linear momentum of the electron just after the co
Strike441 [17]
Momentum is a vector quantity, and is always conserved. Whenever a collision occurs between two objects, the objects behave under the principle of conservation of momentum. Therefore, if an object moves in the direction opposite to its original direction after a collision, then this indicates that the momentum of the colliding object was greater than the object under consideration. 
8 0
3 years ago
Plz help!!!!!<br><br><br> Best answer will get<br> B R A I N L I E S T!!!
SVEN [57.7K]
They spill out chemicals into our air that may be bad for our lungs

7 0
3 years ago
A ski jumper has a mass of 59.6 kg. She is moving with a speed of 23.4 m/s at a height of 44.6 meters above the ground. Determin
Daniel [21]

Hello!

Use the formula:

M = k * p

Data:

M = Mechanic energy

k = Kinetic energy

p = Potencial energy

Descomposing:

M = (0,5*mv²) + (mgh)

Replacing:

M = (0,5 * 59,6 kg * (23,4 m/s)²) + (59,6 kg * 9,81 m/s² * 44,6 m)

M = 16317,28 J + 26076,54 J

M = 42393,82 J

The mechanic energy is <u>42393,82 Joules.</u>

7 0
3 years ago
Other questions:
  • Is the force of gravity stronger on a piece of crumpled paper or a normal piece of flat paper?
    8·1 answer
  • If an electric circuit has 0 A of current running through it then .
    9·1 answer
  • While drag racing out of the parking lot I timed myself at a speed of
    14·1 answer
  • A laser beam of total power 1 mW and wavelength 365 nm is incident on a clean piece of metal in vacuum. The metal has a work fun
    15·1 answer
  • A transformer has a primary voltage of 115 V and a secondary voltage of 24 V. If the number of turns in the primary is 345, how
    6·1 answer
  • Two identical circular, wire loops 48.0 cm in diameter each carry a current of 4.50 A in the same direction. These loops are par
    10·1 answer
  • Pls can anyone help me
    12·1 answer
  • a car accelerate at 9 m/s squared. Assuming the car starts from rest how far will it travel in 10 seconds
    12·1 answer
  • A net force of 15 N is exerted on an encyclopedia to cause it to accelerate at a rate of 5 m/s2. Determine the mass of the encyc
    9·1 answer
  • 25. IF THE ROADWAY IS WET AND THE CAR STARTS TO SKID, YOU SHOULD: A. Slow down by pumping the brakes quickly and firmly B. Slow
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!