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
True [87]
2 years ago
8

A soccer player icks a rock horizontally off a 40m high cliff into a pool f water if the player hears the sound of the splash s

later, what was the inital speeed given to the rock assume the speed of sound in air to be 343?
Physics
1 answer:
Semenov [28]2 years ago
7 0

Answer:

v = 9.936 m/s

Explanation:

given,

height of cliff = 40 m

speed of sound = 343 m/s

assuming that time to reach the sound to the player = 3 s

now,

time taken to fall of ball

t = \sqrt{\dfrac{2s}{g}}

t = \sqrt{\dfrac{2\times 40}{9.8}}

t = 2.857 s

distance

d = v  x t

d = v x 2.875

time traveled by the sound before reaching the player

t_0 = t - t_{fall}

t_0 = 3 - 2.875

t_0 = 0.143 s

distance traveled by the wave in this time'

r = 0.143 x 343

r= 49.05 m

now,

we know.

d² + h² = r²

d² + 40² = 49.05²

d =28.387 m

v x 2.875=28.387 m

v = 9.936 m/s

You might be interested in
Two point charges, with charge magnitudes q and ????, are placed a distance r apart. In this arrangement, each point charge expe
sammy [17]

Answer:

1)  Q ’= 8 Q ,  2)    q ’= 16 q ,  3)   r ’= ¾ r

Explanation:

For this exercise we will use Coulomb's law

      F = k q Q / r²

It asks us to calculate the change of any of the parameters so that the force is always F

Original values

                q, Q, r

Scenario 1

      q ’= 2q

       r ’= 4r

     F = k q ’Q’ / r’²

we substitute

     F = k 2q Q ’/ (4r)²

     F = k 2q Q '/ 16r²

we substitute the value of F

      k q Q / r² = k q Q '/ 8r²

       Q ’= 8 Q

Scenario 2

       Q ’= Q

       r ’= 4r

we substitute

      F = k q ’Q / 16r²

      k q Q / r² = k q’ Q / 16 r²

      q ’= 16 q

Scenario 3

      q ’= 3/2 q

      Q ’= ⅜ Q

we substitute

        k q Q r² = k (3/2 q) (⅜ Q) / r’²

        r’² = 9/16 r²

        r ’= ¾ r

6 0
3 years ago
6. (a) Suppose the earth is revolving round the sun in a circular orbit of radius one b astronomical unit (1.5% 10 km). Find the
kkurt [141]

Answer:

tough

ques

Explanation:

5 0
1 year ago
. Consider the equation =0+0+02/2+03/6+04/24+5/120, where s is a length and t is a time. What are the dimensions and SI units of
Olegator [25]

Answer:

See Explanation

Explanation:

Given

s=s_0+v_0t+\frac{a_0t^2}{2}+ \frac{j_0t^3}{6}+\frac{S_0t^4}{24}+\frac{ct^5}{120}

Solving (a): Units and dimension of s_0

From the question, we understand that:

s \to L --- length

t \to T --- time

Remove the other terms of the equation, we have:

s=s_0

Rewrite as:

s_0=s

This implies that s_0 has the same unit and dimension as s

Hence:

s_0 \to L --- dimension

s_o \to Length (meters, kilometers, etc.)

Solving (b): Units and dimension of v_0

Remove the other terms of the equation, we have:

s=v_0t

Rewrite as:

v_0t = s

Make v_0 the subject

v_0 = \frac{s}{t}

Replace s and t with their units

v_0 = \frac{L}{T}

v_0 = LT^{-1}

Hence:

v_0 \to LT^{-1} --- dimension

v_0 \to m/s --- unit

Solving (c): Units and dimension of a_0

Remove the other terms of the equation, we have:

s=\frac{a_0t^2}{2}

Rewrite as:

\frac{a_0t^2}{2} = s_0

Make a_0 the subject

a_0 = \frac{2s_0}{t^2}

Replace s and t with their units [ignore all constants]

a_0 = \frac{L}{T^2}\\

a_0 = LT^{-2

Hence:

a_0 = LT^{-2 --- dimension

a_0 \to m/s^2 --- acceleration

Solving (d): Units and dimension of j_0

Remove the other terms of the equation, we have:

s=\frac{j_0t^3}{6}

Rewrite as:

\frac{j_0t^3}{6} = s

Make j_0 the subject

j_0 = \frac{6s}{t^3}

Replace s and t with their units [Ignore all constants]

j_0 = \frac{L}{T^3}

j_0 = LT^{-3}

Hence:

j_0 = LT^{-3} --- dimension

j_0 \to m/s^3 --- unit

Solving (e): Units and dimension of s_0

Remove the other terms of the equation, we have:

s=\frac{S_0t^4}{24}

Rewrite as:

\frac{S_0t^4}{24} = s

Make S_0 the subject

S_0 = \frac{24s}{t^4}

Replace s and t with their units [ignore all constants]

S_0 = \frac{L}{T^4}

S_0 = LT^{-4

Hence:

S_0 = LT^{-4 --- dimension

S_0 \to m/s^4 --- unit

Solving (e): Units and dimension of c

Ignore other terms of the equation, we have:

s=\frac{ct^5}{120}

Rewrite as:

\frac{ct^5}{120} = s

Make c the subject

c = \frac{120s}{t^5}

Replace s and t with their units [Ignore all constants]

c = \frac{L}{T^5}

c = LT^{-5}

Hence:

c \to LT^{-5} --- dimension

c \to m/s^5 --- units

4 0
3 years ago
Kevin jumps straight up in the air to a height of 1 meter.At the top of his jump, he has potential energy of 1,000 joules.Answer
Llana [10]
Gravitational potential energy can be given by the equation
PE = mgh
where m is the mass,
g is the gravitational constant 9.81 or 10 depending on rounding
and h is the height

well weight is a force equiavlent to
W= m*g

so comparing that to the potential energy equation, divide the potential energy by the height and you will get weight in Newtons


3 0
3 years ago
A driver entering the outskirts of a city takes her foot off the accelerator so that the car slows down from 90 km/h to 50 km/h
Varvara68 [4.7K]

Answer:

Explanation:

a = (vf - vi) / t

a = (50 - 90) / 10.0

a = -4 km/h/s(1000 m/km / 3600 s/h)

a = - 1.11 m/s²

5 0
2 years ago
Other questions:
  • An airplane flies 21 km in 30 minutes. What is its average speed in kilometers per hour?
    10·2 answers
  • Spitting cobras can defend themselves by squeezing muscles around their venom glands to squirt venom at an attacker. Suppose a s
    12·1 answer
  • Which term describes the amount of heat needed to change 1 kg of a substance from solid to liquid at its melting point? A. Speci
    13·1 answer
  • A particle moves along a straight line and its position at time t is given by
    6·1 answer
  • Which of the three types of equations follows the law of conservation of mass?
    15·1 answer
  • Lead has a density of 11. 5 g/cm³. A rectangular block of lead measures 7 cm x 5 cm x 2 cm.
    8·1 answer
  • How can I solve the following statement?
    8·1 answer
  • Need help in the question that is down
    10·1 answer
  • 100!!! POINTS PLZ HELPPPPPP
    10·1 answer
  • Please help someone. A generator consumes 147 joules of energy in fuel and produces 75 joules of energy
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!