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
FrozenT [24]
3 years ago
7

A ball is thrown with an initial speed of 20m/s at an angle of 60 to the ground. If air resistance is negligible, what is the ba

ll ‘s speed at the instant it reaches its maximum height from the ground.
Physics
1 answer:
torisob [31]3 years ago
4 0

Answer:

when a ball is thrown to the air and it attains it maximum height it's value is 0.

Explanation:

Therefore

V = Ucos angle

V = 20 cos 60°

V = 20 x0. 5

V= 10m/s

You might be interested in
A small meteorite with mass of 1 g strikes the outer wall of a communication satellite with a speed of 2Okm/s (relative to the s
strojnjashka [21]

Answer:

The energy coverted to heat is 200 kilojoules.

Explanation:

GIven the absence of external forces exerted both on the small meteorite and on the communication satellite, the Principle of Linear Momentum is considered and let suppose that collision is completely inelastic and that satellite is initially at rest. Hence, the expression for the satellite-meteorite system:

m_{M}\cdot v_{M} + m_{S}\cdot v_{S} = (m_{M}+m_{S})\cdot v

Where:

m_{M}, m_{S} - Masses of the small meteorite and the communication satellite, measured in kilograms.

v_{M}, v_{S} - Speeds of the small meteorite and the communication satellite, measured in meters per second.

v - Final speed of the satellite-meteorite system, measured in meters per second.

The final speed of the satellite-meteorite system is cleared:

v = \frac{m_{M}\cdot v_{M}+m_{S}\cdot v_{S}}{m_{M}+m_{S}}

If m_{M} = 1\times 10^{-3}\,kg, m_{S} = 200\,kg, v_{M} = 20000\,\frac{m}{s} and v_{S} = 0\,\frac{m}{s}, the final speed is now calculated:

v = \frac{(1\times 10^{-3}\,kg)\cdot \left(20000\,\frac{m}{s} \right)+(200\,kg)\cdot \left(0\,\frac{m}{s} \right)}{1\times 10^{-3}\,kg+200\,kg}

v = 0.1\,\frac{m}{s}

Which means that the new system remains stationary and all mechanical energy from meteorite is dissipated in the form of heat. According to the Principle of Energy Conservation and the Work-Energy Theorem, the change in the kinetic energy is equal to the dissipated energy in the form of heat:

K_{S} + K_{M} - K - Q_{disp} = 0

Q_{disp} = K_{S}+K_{M}-K

Where:

K_{S}, K_{M} - Initial translational kinetic energies of the communication satellite and small meteorite, measured in joules.

K - Kinetic energy of the satellite-meteorite system, measured in joules.

Q_{disp} - Dissipated heat, measured in joules.

The previous expression is expanded by using the definition for the translational kinetic energy:

Q_{disp} = \frac{1}{2}\cdot [m_{M}\cdot v_{M}^{2}+m_{S}\cdot v_{S}^{2}-(m_{M}+m_{S})\cdot v^{2}]

Given that m_{M} = 1\times 10^{-3}\,kg, m_{S} = 200\,kg, v_{M} = 20000\,\frac{m}{s}, v_{S} = 0\,\frac{m}{s} and v = 0.1\,\frac{m}{s}, the dissipated heat is:

Q_{disp} = \frac{1}{2}\cdot \left[(1\times 10^{-3}\,kg)\cdot \left(20000\,\frac{m}{s} \right)^{2}+(200\,kg)\cdot \left(0\,\frac{m}{s} \right)^{2}-(200.001\,kg)\cdot \left(0.001\,\frac{m}{s} \right)^{2}\right]Q_{disp} = 200000\,J

Q_{disp} = 200\,kJ

The energy coverted to heat is 200 kilojoules.

4 0
3 years ago
A flatbed truck is supported by its four drive wheels, and is moving with an acceleration of 6.3 m/s2. For what value of the coe
Levart [38]

Answer:

Coefficient of static friction will be equal to 0.642  

Explanation:

We have given acceleration a=6.3m/sec^2

Acceleration due to gravity g=9.8m/sec^2

We have to find the coefficient of static friction between truck and a cabinet will

We know that acceleration is equal to a=\mu g, here \mu is coefficient of static friction and g is acceleration due to gravity

So \mu =\frac{a}{g}=\frac{6.3}{9.8}=0.642

So coefficient of static friction will be equal to 0.642

3 0
3 years ago
How does temperature affect chemical reaction​
Elis [28]
When its temperature increases, the reactants have more kinetic energy so the frequency of effective collision increases, resulting in a faster rate of chemical reaction.
8 0
3 years ago
The steps taken in scientific studies often follow similar patterns. which answer correctly describes the order in which the ste
scZoUnD [109]
OPTION A WOULD BE YOUR ANSWER
7 0
3 years ago
Read 2 more answers
Where is potential energy the greatest on a rollercoaster?
lidiya [134]
On a roller coaster, the greatest potential energy is at the highest point of the roller coaster
4 0
3 years ago
Other questions:
  • A diagram of the carbon-oxygen cycle is shown below.
    11·2 answers
  • What forces contribute to density
    10·1 answer
  • PLEASE HELP ME, I NEED THIS DONE AS SOON AS POSSIBLE.
    11·1 answer
  • During a testing process, a worker in a factory mounts a bicycle wheel on a stationary stand and applies a tangential resistive
    11·1 answer
  • In the formation of the solar system, nearly all of the mass of the solar nebula became
    9·2 answers
  • The density of atmosphere (measured in kilograms/meter3) on a certain planet is found to decrease as altitude increases (as meas
    6·1 answer
  • Two charged objects attract each other with a force of F. What happens to the force between them if one charge is doubled, the o
    8·1 answer
  • If a machine exerts a force of 250N on an object and no work is done, what must have occurred?
    12·1 answer
  • A cellphone charger has a transformer with
    13·1 answer
  • A 0. 060-kg tennis ball, moving with a speed of 5. 82 m/s , has a head-on collision with a 0. 090-kg ball initially moving in th
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!