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
cupoosta [38]
3 years ago
13

A driver of a car took a day trip around the coastline driving at two different speeds. He drove 7070 miles at a slower speed an

d 200200​ miles at a speed 3030 miles per hour faster. If the time spent driving at the faster speed was twicetwice that spent driving at the slower​ speed, find the two speeds during the trip.
Physics
2 answers:
kondor19780726 [428]3 years ago
7 0

Answer:

Slower speed = 70 mph

Faster speed = 100 mph

Explanation:

Let the slower speed be x miles per hour

Then, the faster speed = (x+30) miles per hour

Let the time spent driving at the slower speed (that is, at x mph) = t

Then, time spent driving at the faster speed (that is, at (x+30) mph) = 2t

speed = (distance)/(time)

Distance = speed × time

Distance covered during the slower speed = x × t = xt = 70 (given in the question)

xt = 70 (eqn 1)

At the faster speed

Distance covered = (x+30)(2t) = 2t(x+30)

Distance covered during faster speed = 200 miles

2t(x+30) = 200

2xt + 60t = 200

Recall (eqn 1)

xt = 70

2(70) + 60t = 200

60t = 60

t = 1 hour.

xt = 70

Slower speed = x = 70 mph

Faster speed = (x+30) = 100 mph

babymother [125]3 years ago
5 0

complete question:

A driver of a car took a day trip around the coastline driving at two different speeds. He drove 70 miles at a slower speed and 200​ miles at a speed 30 miles per hour faster. If the time spent driving at the faster speed was twice that spent driving at the slower​ speed, find the two speeds during the trip.

Answer:

slower speed

speed   = 70 miles/hr

Faster speed

speed = 100 miles/hr

Explanation:

The driver took a day trip at two different speed. The first speed was slower while the second was faster.

let the speed be divided into 2

Slower speed

speed = a

distance = 70

speed = distance/time

time = distance/speed

time = 70/a

Faster speed

speed = a + 30

distance = 200

speed = distance/time

time = distance/speed

time = 200/a + 30

Since the faster speed time is twice the slower speed time it can be represented as follows:

2 × 70/a = 200/a + 30

140/a = 200/ a + 30

cross multiply

140a + 140(30) = 200a

4200 = 200a - 140a

4200 = 60a

divide both sides by 60

4200/60 = a

a = 70

Inserting the value of a in the time of the faster speed formula

time = 200/a + 30

time = 200/100

time = 2 hr

slower speed

speed = distance/time

speed = 70/1

speed   = 70 miles/hr

Faster speed

speed = distance/time

speed = 200/2

speed = 100 miles/hr

You might be interested in
What are the forces that act on the ball pushed on the floor​?<br><br>Plss answer
vaieri [72.5K]

Explanation:

The ball, for example, will feel gravity pulling it downward and the ground pushing it upward in the direction it is rolling. (Add this if the ball is rolling on the floor.) Friction is the force that causes the ball to slow down because it acts in the opposite direction that it is moving.

If This Answer Helped You Please Mark Me As Brainliest.

4 0
2 years ago
. A 40.0-kg child standing on a frozen pond throws a 0.500-kg stone to the east with a speed of 5.00 m/s. Neglecting friction be
tamaranim1 [39]

Answer:

Explanation:

A 40kg child throw stone of 0.5kg

At a direction of 5m/s

Recoil can be calculated using recoil of a gun formula

m_1•v_1 + m_2•v_2

m_1•v_1 = -m_2•v_2

The negative sign show that the momentum of the boy is directed oppositely to that of the stone

m_1 Is mass of boy

v_1 is the recoil velocity of the boy

m_2 is mass of stone

v_2 is the velocity of stone

Then,

m_1•v_1 = -m_2•v_2

40•v_1 = -0.5 × 5

40•v_1 = -2.5

v_1 = -2.5 / 40

v_1 = -0.0625 m/s

The recoil velocity of the boy is 0.0625 m/s

6 0
3 years ago
Two speakers in a stereo emit identical pure tones. As you move around in front of the speakers, you hear the sound alternating
BigorU [14]

Answer:

Interference

Explanation:

When two traveling waves traveling waves along the same path are superimposed(combine). The superimposition of these two waves results in the production of a resultant wave which is defined by the net effect of the two waves. Wave interference occurs most types of waves including radio wave, light, acoustic waves and other wave types. Alternating sound between loud and Zero is heard as the two speakers emit identical pure tones because the resultant amplitude after the interference of the two sound waves is the vector sum of each of their amplitudes. A loud sound is heard, when the crest of both waves meets each other and a zero is heard if the crest of one meets the trough of the other as they cancel out.

3 0
3 years ago
. Why are scientific models important? They help scientists prove scientific theories. They help scientists explain complex ques
sdas [7]
The best answer would be the 4th choice. "They help scientists explain concepts that are difficult to observe, this also covers the first answer which helps the scientist to answer complex questions. A scientific model is not used prove scientific laws as they may not always have all the data to prove so, instead it is used to allow them to explain better concepts revolving around science through research and may also allow them to predict results based on the accumulation of data and analyzing the trend of this resulting information.
3 0
3 years ago
Anna pushes a box with a force of 8.00 newtons. She generates a power of 3.00 watts. How much time does it take for Anna to move
QveST [7]
Power is the energy in a system per time.  It will have units of Watts which is equal to joules per second. It can be expressed as:

P = E / t

where E = Force x distance

P = Fd / t
t = Fd / P
t = 8 (9.72) / 3.0
t = 25.92 s
8 0
3 years ago
Read 2 more answers
Other questions:
  • Some plants disperse their seeds when the fruit splits and contracts, propelling the seeds through the air. The trajectory of th
    14·2 answers
  • A girl and a boy are riding on a merry-go-round that is turning at a constant rate. The girl is near the outer edge, and the boy
    12·1 answer
  • Mark all the quarks.a) Proton b) Electron c)Anti-top d) Gluon e) Tau Neutrino
    15·1 answer
  • Which of the following would reduce the resistance of a metal wire?
    8·2 answers
  • How many neutrons does element X have if it's atomic number is 23 and its mass number is 70​
    12·1 answer
  • The velocity of sound on a particular day outside is 331 meters/second. What is the frequency of a tone if it has a wavelength o
    6·2 answers
  • 12. One object has half the mass of another object. The first object also has half the ---.
    7·1 answer
  • An object wants to maintain its state of motion because it has mass. True or false
    13·1 answer
  • You weight is result of the gravitational force of earth on your body what is the cor responding reaction force
    10·1 answer
  • The figure shows the electric field inside a cylinder of radius R= 3.2 mm. The field strength is increasing with time as E= 1.4
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!