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
Eva8 [605]
3 years ago
8

A car travels from Boston to Hartford in 4 hours. The two cities are 240 kilometers apart. What was the average speed of the car

during the trip? A. 4 km/hour B. 960 km/hour C. 60 km/hour
Physics
1 answer:
Y_Kistochka [10]3 years ago
6 0

Answer:

Average speed is 60 km/hour

Explanation:

When we need to calculate average speed, we use this equation:

V = \frac{x_{f} - x_{o}}{t_{f} - t_{o}}

Where:   x_{o} = 0 km   position at the beginning

              x_{f} = 240 km   at the end

              t_{o} = 0 hours

              t_{f} = 4 hours

Then:     V = \frac{240 km - 0 km}{4 hours - 0 hours}

              V = \frac{240 km}{4 hours}

Finally    V = 60 km/hour

You might be interested in
The driver of a car traveling at 22.8 m/s applies the brakes and undergoes a constant deceleration of 2.95 m/s 2 . How many revo
a_sh-v [17]

Answer:

70 revolutions

Explanation:

We can start by the time it takes for the driver to come from 22.8m/s to full rest:

t = \Delta v/a = (22.8 - 0)/2.95 = 7.73 s

The tire angular velocity before stopping is:

\omega_0 = v/r = 22.8 / 0.2 = 114 rad/s

Also its angular decceleration:

\alpha = a / r = 2.95/0.2 = 14.75 rad/s^2

Using the following equation motion we can findout the angle it makes during the deceleration:

\omega^2 - \omega_0^2 = 2\alpha\Delta \theta

where \omega = 0 m/s is the final angular velocity of the car when it stops, \omega_0 = 114rad/s is the initial angular velocity of the car \alpha = 14.75 rad/s2 is the deceleration of the can, and \Delta \theta is the angular distance traveled, which we care looking for:

-114^2 = 2*(-14.75)*\Delta \theta

\Delta \theta = 440rad or 440/2π = 70 revelutions

4 0
3 years ago
Describe the effects of heat​
astraxan [27]

1. Heat raises the temperature.

2. It increases volume.

3. It changes state.

4. Brings about chemical action.

5. Changes physical properties.

<h3>Hope this helps :)</h3>
8 0
2 years ago
Read 2 more answers
A scientific hypothesis must be related to nature and be..
PSYCHO15rus [73]

Answer:

A scientific hypothesis must be tetable so it can become a scientific theory.

Explanation: I think

8 0
3 years ago
Two mass m1 and m2 lie on a frictionless surface. Between the two masses is a compressed spring, with spring constant k. The sys
max2010maxim [7]

Answer:

The spring was compressed the following amount:

\Delta x=\sqrt{ \frac{m_1\,v_1^2+ m_2\,v_2^2}{k} }

Explanation:

Use conservation of energy between initial and final state, considering that the surface id frictionless, and there is no loss in thermal energy due to friction. the total initial energy is the potential energy of the compressed spring (by an amount \Delta x), and the total final energy is the addition of the kinetic energies of both masses:

E_i=\frac{1}{2} k\,(\Delta x)^2\\\\E_f=\frac{1}{2} m_1\,v_1^2+\frac{1}{2} m_2\,v_2^2

E_i=E_f\\

\frac{1}{2} k\,(\Delta x)^2=\frac{1}{2} m_1\,v_1^2+\frac{1}{2} m_2\,v_2^2\\k\,(\Delta x)^2=m_1\,v_1^2+ m_2\,v_2^2\\(\Delta x)^2=\frac{m_1\,v_1^2+ m_2\,v_2^2}{k} \\\Delta x=\sqrt{ \frac{m_1\,v_1^2+ m_2\,v_2^2}{k} }

8 0
3 years ago
A 10.0-kg box starts at rest and slides 3.5 m down a ramp inclined at an angle of 10° with the horizontal. If there is no fricti
Alenkinab [10]

Answer:

v_f = 3.45 m/s

Explanation:

As we know that box was initially at rest

so here work done by all forces on the box = change in its kinetic energy

so we will have

mg sin\theta L = \frac{1}{2}mv_f^2 - \frac{1}{2}mv_i^2

now we have

m = 10 kg

\theta = 10^0

L = 3.5 m

so we will have

10(9.81)sin10 \times 3.5 = \frac{1}{2}(10)(v_f^2 - 0)

2(9.81) sin10 \times 3.5 = v_f^2

so final speed is given as

v_f = 3.45 m/s

6 0
3 years ago
Other questions:
  • How do scientists interpret data?
    7·1 answer
  • When the quantity q is greater than zero, __________ is added to the system?
    8·1 answer
  • A charge Q is transferred from an initially uncharged plastic ball to an identical ball 17 cm away. The force of attraction is t
    7·1 answer
  • A 10000 kg rocket blasts off vertically from the launch pad with a constant upward of 2.25 m/s2 and feels no appreciable air res
    12·1 answer
  • Need help on this please
    8·1 answer
  • Money is useful to people because it is __________.Select one of the options below as your answer:
    15·2 answers
  • What is the latin name for the hydra constellation
    8·1 answer
  • Can vectors be strung together?
    11·1 answer
  • HELP PLS! :/
    6·1 answer
  • S.I unit for moment of inertia of a fly wheel​
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!