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
erastova [34]
3 years ago
6

Two cars are traveling along a straight line in the same direction, the lead car at 24.7m/s and the other car at 29.9m/s. at the

moment the cars are 38.1m apart, the lead driver applies the brakes, causing her car to have an acceleration of -1.96m/s2. how long does it take for the lead car to stop? (in s)
Physics
1 answer:
sattari [20]3 years ago
7 0

Answer: 12.6 s

We would use the equation of motion:

v-u=at

where v is the final velocity, u is the initial velocity, a is the acceleration and t is the time taken.

It is given that the lead car has an initial velocity, u=24.7\hspace{1mm} m/s. It decelerates with a=-1.96 \hspace{1mm} m/s^{2} to stop (v=0). we need to calculate the time taken by the lead car to stop.

\Rightarrow t=\frac{v-u}{a}\\ \Rightarrow t=\frac{0-24.7}{-1.96}=12.6\hspace{1mm} s

You might be interested in
A 15.0 Ohms resistor is connected in series to a 120V generator and two 10.0 Ohms resistors that are connected in parallel to ea
Nostrana [21]

Hi there! :)

Reference the diagram below for clarification.

1.

We must begin by knowing the following rules for resistors in series and parallel.

In series:
R_T = R_1 + R_2 + ... + R_n

In parallel:
\frac{1}{R_T} = \frac{1}{R_1} + \frac{1}{R_2} + ... + \frac{1}{R_n}

We can begin solving for the equivalent resistance of the two resistors in parallel using the parallel rules.

\frac{1}{R_{T, parallel}} = \frac{1}{10} + \frac{1}{10}\\\\\frac{1}{R_{T, parallel}} = \frac{2}{10} = \frac{1}{5}\\\\R_{T, parallel} = 5\Omega

Now that we have reduced the parallel resistors to a 'single' resistor, we can add their equivalent resistance with the other resistor in parallel (15 Ohm) using series rules:
R_T = 15 + 5\\\\\boxed{R_T = 20 \Omega}

2.

We can use Ohm's law to solve for the current in the circuit.

i = \frac{V}{R_T}\\\\i = \frac{120}{20} = \boxed{6 A}

3.

For resistors in series, both resistors receive the SAME current.

Therefore, the 15Ω resistor receives 6A, and the parallel COMBO (not each individual resistor, but the 5Ω equivalent when combined) receives 6A.

In this instance, since both of the resistors in parallel are equal, the current is SPLIT EQUALLY between the two. (Current in parallel ADDS UP). Therefore, an even split between 2 resistors of 6 A is <u>3A for each 10Ω resistor</u>.

4.

Since the 15.0 Ω resistor receives 6A, we can use Ohm's Law to solve for voltage.

V = iR\\\\V = (6)(15) = \boxed{90 V}

4 0
1 year ago
What is the wavelength of a 10 Hz wave that travels with a speed of 5 m/s?
garik1379 [7]
B

V= f x lambda
V= 5m/s
F = 10hz
Lambda = ?
5 = 10 x lamba
5 /10 = lambda
Wavelength =0.5
8 0
2 years ago
7. An object can be accelerating even if its speed is
steposvetlana [31]

Answer:

I think that the answer might be d

4 0
2 years ago
Read 2 more answers
a pendulum, 2.0 m in length, is released with a push when the string is at an angle of 25 o from the vertical. if the initial sp
stiks02 [169]

Answer:

1 / 2 m v^2 = L m g (1 - cos θ)

This is the KE due to the pendulum falling from a 25 deg displacement

v^2 = 2 L g (1 - cos 25) = 2 * 2 * 9.8 (1 - .906) = 3.67 m^2/s^2

v = 1.92 m/s      this is the speed due to an initial displacement of 25 deg

Its speed at the bottom would then be

1.92 + 1.2 = 3.12 m/s   since it gains 1.92 m/s from its initial displacement

3 0
1 year ago
A spring with spring constant of 26 N/m is stretched 0.22 m from its equilibrium position. How much work must be done to stretch
Evgen [1.6K]

Answer:

1.503 J

Explanation:

Work done in stretching a spring = 1/2ke²

W = 1/2ke²........................... Equation 1

Where W = work done, k = spring constant, e = extension.

Given: k = 26 N/m, e = (0.22+0.12), = 0.34 m.

Substitute into equation 1

W = 1/2(26)(0.34²)

W = 13(0.1156)

W = 1.503 J.

Hence the work done to stretch it an additional 0.12 m = 1.503 J

8 0
3 years ago
Other questions:
  • Two long, parallel wires are separated by a distance of 2.30 cm . The force per unit length that each wire exerts on the other i
    5·1 answer
  • Definition for compression and rarefraction
    11·2 answers
  • What 3 places on your body do not grow hair
    15·2 answers
  • the amount of water returning to the earth through precipitation is blank the amount of water leaving the earth through evaporat
    6·1 answer
  • Objects 1 and 2 attract each other with a electrostatic force
    15·2 answers
  • The gravitational force between two spheres in outer space is 1000 n. how large would this force be if the mass of each sphere w
    15·1 answer
  • The light bulb in your room is not very bright. You want to use a concave mirror to direct its illumination into a tight, parall
    13·1 answer
  • How to calculate average breaking force physics
    15·1 answer
  • A 70kg car drives through a curve with radius 50m. What is the minimum angle the road should be tilted to keep the car on the ro
    10·1 answer
  • A musical tone sounded on a pi has frequency of 410 Hz and a wavelength of 0.80 m.
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!