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
spin [16.1K]
3 years ago
9

A motorist enters a freeway at 45 km/h and accelerates uniformly to 99 km/h. From the odometer in the car, the motorist knows th

at she traveled 0.2 km while accelerating. Determine (a) the acceleration of the car, (b) the time required to reach 99 km/h
Physics
1 answer:
Marat540 [252]3 years ago
5 0

Answer:

a)  19440 km/h²

b) 10 sec

Explanation:

v₀ = initial velocity of the car = 45 km/h

v = final velocity achieved by the car = 99 km/h

d = distance traveled by the car while accelerating = 0.2 km

a = acceleration of the car

Using the kinematics equation

v² = v₀² + 2 a d

99² = 45² + 2 a (0.2)

a = 19440 km/h²

b)

t = time required to reach the final velocity

Using the kinematics equation

v = v₀ + a t

99 = 45 + (19440) t

t = 0.00278 h

t = 0.00278 x 3600 sec

t = 10 sec

You might be interested in
Guitar string has an overall length of 1.22 m and a total mass of 3.5 g before being strung on a guitar. Once it is used on the
ikadub [295]

Answer:

Fundamental frequency= 174.5 hz

Explanation:

We know

fundamental frequency=\frac{velocity}{2 *length}

velocity =\sqrt{\frac{tension}{mass per unit length} }

mass per unit length=\frac{3.5}{1000*1.22}=0.00427\frac{kg}{m}

Now calculating velocity v=\sqrt{\frac{255}{0.00427} }

                                           =244.3\frac{m}{sec}

Distance between two nodes is 0.7 m.

Plugging these values into to calculate frequency

f = \frac{244.3}{2 *0.7} =174.5 hz

6 0
4 years ago
.A coin rolls off the edge of a table. The coin
geniusboy [140]

Answer:

Apply the following formulae horizontally And get A value for time

Remember horizontal acceleration is zero

s  = ut +  \frac{1}{2}a {t}^{2}   \\ 0.8 = 1.7 \times t \\  \frac{0.8}{1.7}  = t \\ t = 0.47s

and then to find the height apply the same above equation vertically...remember vertical initial velocity is zero

s = ut +  \frac{1}{2} a {t}^{2}  \\ s =  \frac{1}{2}  \times 10 \times (0.47) ^{2}  \\ s = 1.1045m

5 0
3 years ago
Select the correct answer from each drop-down menu.
-Dominant- [34]

Answer:

And the force of ( Attraction or repulsion) between the poles A and D ( maximum or minimum)

4 0
3 years ago
Read 2 more answers
Est ce qu’un cricket c’est un consommateur
Sholpan [36]

Answer:

Oui

Explanation:

7 0
3 years ago
g Incandescent bulbs generate visible light by heating up a thin metal filament to a very high temperature so that the thermal r
Naddika [18.5K]

Answer:

2577 K

Explanation:

Power radiated , P = σεAT⁴ where σ = Stefan-Boltzmann constant = 5.6704 × 10⁻⁸ W/m²K⁴, ε = emissivity of bulb filament = 0.8, A = surface area of bulb = 30 mm² = 30 × 10⁻⁶ m² and T = operating temperature of filament.

So, T = ⁴√(P/σεA)

Since P = 60 W, we substitute the vales of the variables into T. So,

T = ⁴√(P/σεA)

= ⁴√(60 W/(5.6704 × 10⁻⁸ W/m²K⁴ × 0.8 × 30 × 10⁻⁶ m²)

= ⁴√(60 W/(136.0896 × 10⁻¹⁴ W/K⁴)

= ⁴√(60 W/(13608.96 × 10⁻¹⁶ W/K⁴)

= ⁴√(0.00441 × 10¹⁶K⁴)

= 0.2577 × 10⁴ K

= 2577 K

6 0
3 years ago
Other questions:
  • When the posted speed limit is 70 mph, the minimum speed limit is ___________ mph.
    14·2 answers
  • 50 J of work was performed in 20 seconds. How much power was used to do this task?
    9·2 answers
  • Scientists classify rocks by
    7·1 answer
  • How much current is flowing in a wire 4.40 mm long if the maximum force on it is 0.575 NN when placed in a uniform 0.0550-TT fie
    14·1 answer
  • Based on the graph below, what prediction can we make about the acceleration when the force is 0 newtons? A. It will be 0 meters
    15·2 answers
  • What’s is the movement of one object around another
    14·1 answer
  • ASAP FIRST TO ANSWER CORRECTLY WILL BE BRAINLIEST
    6·1 answer
  • Which device converts chemical energy directly into electrical energy?
    5·2 answers
  • A student is trying to demonstrate static electricity, so they rub two identical balloons with a neutral rabbit fur to give them
    7·1 answer
  • using dimensional analysis find the relation between the velocities of transverse waves produced from the vibration of thin homo
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!