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
just olya [345]
3 years ago
8

A soccer player kicks a ball horizontally off a 40.0-m-high cliff into a pool of water. If the player hears the sound of the spl

ash 3.00 s later, what was the initial speed given to the rock? Assume the speed of sound in air is 343 m/s. Determine the speed of the ball immediately before it reaches the pool of water.
Physics
1 answer:
JulijaS [17]3 years ago
8 0

the speed of the ball before it reaches the pool of water would be 9.91 m/s.

You might be interested in
Which action best demonstrates the transformation of mechanical energy to heat energy and sound energy?
MrMuchimi

Answer:

striking a hammer on a nail

7 0
3 years ago
A balloon filled with helium gas has an average density of Q,-0.41 kg/m'. The density of the air is Qa-1.23 kg/m3. The volume of
Citrus2011 [14]

Answer:

a) (Qa*g*Vb)-(Qh*Vb*g)=(Qh*Vb*a)\\where \\g=gravity [m/s^2]\\a=acceleration [m/s^2]

b) a = 19.61[m/s^2]

Explanation:

The total mass of the balloon is:

massball=densityheli*volumeheli\\\\massball=0.41 [kg/m^3]*0.048[m^3]\\massball=0.01968[kg]\\\\

The buoyancy force acting on the balloon is:

Fb=densityair*gravity*volumeball\\Fb=1.23[kg/m^3]*9.81[m/s^2]*0.048[m^3]\\Fb=0.579[N]

Now we need to make a free body diagram where we can see the forces that are acting over the balloon and determinate the acceleration.

In the attached image we can see the free body diagram and the equation deducted by Newton's second law

6 0
2 years ago
Awnser these pls they r for middle schoolers lol
soldi70 [24.7K]

Answer:

Find the set of value of x Find the set of value of x which satisfy the inequality 2r2- 5x 2 18which satisfy the inequality 2r2- Find the set of value of x which satisfy the inequality 2r2- 5x 2 185x 2 18

8 0
2 years ago
A large rocket has a mass of 2.00×10⁶ kg at takeoff, and its engines produce a thrust of 3.50×10⁷ N. Find its initial accelerati
Kazeer [188]

Answer:

17.5 m/s²

1.90476 seconds

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration

Force

F=ma\\\Rightarrow a=\frac{F}{m}\\\Rightarrow a=\frac{3.5\times 10^7}{2\times 10^6}\\\Rightarrow a=17.5\ m/s^2

Initial acceleration of the rocket is 17.5 m/s²

v=u+at\\\Rightarrow \frac{120}{3.6}=0+17.5t\\\Rightarrow t=\frac{\frac{120}{3.6}}{17.5}=1.90476\ s

Time taken by the rocket to reach 120 km/h is 1.90476 seconds

Change in the velocity of a rocket is given by the Tsiolkovsky rocket equation

\Delta v=v_{e}\ln \frac{m_0}{m_f}

where,

m_0 = Initial mass of rocket with fuel

m_f = Final mass of rocket without fuel

v_e = Exhaust gas velocity

Hence, the change in velocity increases as the mass decreases which changes the acceleration

4 0
2 years ago
A 25.0-kg child is standing at the edge of a horizontal merry-go-round with a radius of 2.40 m and a moment of inertia of 356 kg
motikmotik

Answer:

\omega_{f}=1.634\ rad/s  

Explanation:

given,  

diameter of merry - go - round = 2.40 m  

moment of inertia = I = 356 kg∙m²

speed of the merry- go-round = 1.80 rad/s

mass of child = 25 kg  

initial angular momentum of the system  

L_i = I\omega_i  

L_i =356\times 1.80  

L_i =640.8\ kg.m^2/s  

final angular momentum of the system  

L_f = (I_{disk}+mR^2)\omega_{f}  

L_f = (356 + 25\times 1.2^2)\omega_{f}  

L_f= (392)\omega_{f}  

from conservation of angular momentum  

L_i = L_f  

640.8= (392)\omega_{f}  

\omega_{f}=1.634\ rad/s  

8 0
2 years ago
Read 2 more answers
Other questions:
  • if spiderman runs and jumps horizontally from the top of a 200m high building, what does he need his velocity to be to land on a
    5·1 answer
  • The maximum speed of a mass m on an oscillating spring is vmax . what is the speed of the mass at the instant when the kinetic a
    5·1 answer
  • When converting from a smaller to a larger unit of measurement, you move the _______ to the right. A. second number B. ratio C.
    9·2 answers
  • Counseling psychologists typically handle severe psychological disorders.
    12·2 answers
  • A video game includes an asteroid that is programmed to move in a straight line across a 17-inch monitor according to the equati
    9·1 answer
  • Consider the activity and specificity of the three enzymes. Pepsin is most active in the human ________ and helps to digest ____
    10·2 answers
  • When density increases, what happens to the number of molecules in a volume of air?
    5·1 answer
  • What is your wheel and axle
    7·2 answers
  • two car moving in the same direction have speed of 100km/h-1 and 130km/h.what is the resultant of velocity .shoe carnival in the
    13·1 answer
  • What is unusual about the results of mass determinations of clusters of galaxies?
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!