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
Darina [25.2K]
1 year ago
10

A car moving with constant acceleration covers the distance between two points 120 m apart in a time of 8.0 s. its speed at the

second point is 12 m/s. what is the speed of the car at the first point?
Physics
1 answer:
Shalnov [3]1 year ago
7 0

The speed of the car at the first point is 18 m/s.

How do we calculate the initial speed?

The equation we can be used for finding the speed of the first point is:

         ⇒ Δx = ½ (v + v₀)t

From this we can easily calculate v₀ i.e,

        ⇒ v₀ = 2Δx/t - v

According to the question it is given that,

Distance between two points is , Δx =120 m,

Time t = 8.0 s,

Speed at second point is, v = 12 m/s,

Speed at first point is, v₀ = ?

From above formula,

 ⇒  v₀ = 2Δx/t - v

           = 2×120/8 - 12

           = 240-96/8

           = 144/8

           = 18 m/s

Therefore the speed at first point is 18 m/s.

To know more about the calculation of speed, visit the given link:

brainly.com/question/19905871

#SPJ4

You might be interested in
How is photon energy calculated? (choose 2)
raketka [301]
Using Placks’s constant and frequency
5 0
3 years ago
A bike that is coasting down a steep hill increases its speed from 8.0 m/s to 14 m/s. The length of the hill is 55 meters. How m
masya89 [10]

t=5s

it was correct on my do-now

so I hope it was useful for you

8 0
3 years ago
Read 2 more answers
A diffusion couple composed of two silver– gold alloys is formed; these alloys have compositions of 98 wt% Ag–2 wt% Au and 95 wt
jeyben [28]

Answer:

for this problem, 2.5 = (5+2/2)-(5-2/2)erf (50×10-6m/2Dt)

It now becomes necessary to compute the diffusion coefficient at 750°C (1023 K) given that D0= 8.5 ×10-5m2/s and Qd= 202,100 J/mol.

we have D= D0exp( -Qd/RT)

=(8.5×105m2/s)exp(-202,100/8.31×1023)

= 4.03 ×10-15m2/s

4 0
4 years ago
A quarterback throws a football with an angle of elevation 55° and speed 60 ft/s. Find the horizontal and vertical components o
EastWind [94]

Answer:

The horizontal component of the velocity vector is;

vh = 34.4 ft/s

The vertical component of the velocity vector is;

vy = 49.1 ft/s

Explanation:

Given;

Velocity of football v = 60 ft/s

Angle of elevation ∅ = 55°

The horizontal component of the velocity vector is;

vh = vcos∅

Substituting the values;

vh = 60cos55°

vh = 34.41458618106 ft/s

vh = 34.4 ft/s

The vertical component of the velocity vector is;

vy = vsin∅

Substituting the values;

vy = 60sin55°

vy = 49.14912265733 ft/s

vy = 49.1 ft/s

7 0
3 years ago
An electron is moving through an (almost) empty universe at a speed of 628 km,/s toward the only other object in the universe —
sattari [20]

Answer:

  r = 2,026 10⁹ m  and   T = 2.027 10⁴ s

Explanation:

For this exercise let's use Newton's second law

        F = m a

where the force is electric

        F = k \frac{q_1q_2}{r^2}

Acceleration is centripetal

        a = v² / r

we substitute

        k \frac{q_1q_2}{r^2} = m \frac{v^2}{r}

        r = k \frac{q_1q_2}{m \  v^2}          (1)

let's look for the charge in the insulating sphere

          ρ = q₂ / V

          q₂ = ρ V

the volume of the sphere is

         v = 4/3 π r³

we substitute

        q₂ = ρ \frac{4}{3} π r³

        q₂ = 3 10⁻⁹ \frac{4}{3} π 4³

        q₂ = 8.04 10⁻⁷ C

let's calculate the radius with equation 1

        r = 9 10⁹  1.6 10⁻¹⁹  8.04 10⁻⁷ /(9.1  10⁻³¹ 628 10³)

        r = 2,026 10⁹ m

this is the radius of the electron orbit around the charged sphere.

Since the orbit is circulating, the speed (speed modulus) is constant, we can use the uniform motion ratio

        v = x / t

the distance traveled in a circle is

        x = 2π r

In this case, time is the period

        v = 2π r /T

        T = 2π r /v

let's calculate

        T = 2π 2,026 10⁹/628 103

        T = 2.027 10⁴ s

4 0
3 years ago
Other questions:
  • ) A 100-g ball falls from a window that is 12 m above ground level and experiences no significant air resistance as it falls. Wh
    11·1 answer
  • Susan
    9·1 answer
  • Find the amplitude (in m) of such a sound wave if its frequency is 800.0 Hz, the density of air is 1.29 kg/m3 and the speed of s
    10·1 answer
  • Amanda goes shopping for light bulbs. In the light bulb aisle, she finds the following incandescent light bulbs. Can you help he
    15·1 answer
  • For your senior project, you would like to build a cyclotron that will accelerate protons to 10% of the speed of light. The larg
    15·1 answer
  • In a hydroelectric dam, water falls 35.0 m and then spins a turbine to generate electricity. Suppose the dam is 80% efficient at
    6·1 answer
  • More recent findings of children with exceptionally high IQs _
    6·1 answer
  • An object with a density of 0.85 g/cc is dropped into each of the two beakers shown below. Beaker 1 has a density of 0.5 g/cc. B
    14·1 answer
  • Why does ice float on water? A. The temperature of ice is lower than the temperature of water. B. The temperature of water and i
    9·2 answers
  • A machine lifts a 44,760 newton crate 2 meters into the air in 10 seconds. How many horsepower does the machine
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!