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
Ganezh [65]
3 years ago
7

James threw a ball vertically upward with a velocity of 41.67ms-1 and after 2 second David threw a ball vertically upward with a

velocity of 55.56ms-1.When the balls will be at the same height?
Physics
1 answer:
Reptile [31]3 years ago
4 0

Answer:

When have passed 3.9[s], since James threw the ball.

Explanation:

First, we analyze the ball thrown by James and we will find the final height and velocity by the time two seconds have passed.

We'll use the kinematics equations to find these two unknowns.

y=y_{0} +v_{0} *t+\frac{1}{2} *g*t^{2} \\where:\\y= elevation [m]\\y_{0}=initial height [m]\\v_{0}= initial velocity [m/s] =41.67[m/s]\\t = time passed [s]\\g= gravity [m/s^2]=9.81[m/s^2]\\Now replacing:\\y=0+41.67 *(2)-\frac{1}{2} *(9.81)*(2)^{2} \\\\y=63.72[m]\\

Note: The sign for the gravity is minus because it is acting against the movement.

Now we can find the velocity after 2 seconds.

v_{f} =v_{o} +g*t\\replacing:\\v_{f} =41.67-(9.81)*(2)\\\\v_{f}=22.05[m/s]

Note: The sign for the gravity is minus because it is acting against the movement.

Now we can take these values calculated as initial values, taking into account that two seconds have already passed. In this way, we can find the time, through the equations of kinematics.

y=y_{o} +v_{o} *t-\frac{1}{2} *g*t^{2} \\y=63.72 +22.05 *t-\frac{1}{2} *(9.81)*t^{2} \\\\y=63.72 +22.05 *t-4.905*t^{2} \\

As we can see the equation is based on Time (t).

Now we can establish with the conditions of the ball launched by David a new equation for y (elevation) in function of t, then we match these equations and find time t

y=y_{o} +v_{o} *t+\frac{1}{2} *g*t^{2} \\where:\\v_{o} =55.56[m/s] = initial velocity\\y_{o} =0[m]\\now replacing\\63.72 +22.05 *t-(4.905)*t^{2} =0 +55.56 *t-(4.905)*t^{2} \\63.72 +22.05 *t =0 +55.56 *t\\63.72 = 33.51*t\\t=1.9[s]

Then the time when both balls are going to be the same height will be when 2 [s] plus 1.9 [s] have passed after David throws the ball.

Time = 2 + 1.9 = 3.9[s]

You might be interested in
What do the best conductors have in common?
tensa zangetsu [6.8K]

Answer:

A super conductor is a perfect conductor that has zero resistance. It doesn't just have very low resistance and conducts electricity well, it has ZERO resistance and conducts electricity perfectly with no losses at all

6 0
2 years ago
Read 2 more answers
In classical physics, consider a 2 kg block hanging on a spring with a spring constant of 50 N/m. Ignore air resistance. The blo
RUDIKE [14]

Answer:

v = 0

Explanation:

This problem can be solved by taking into account:

- The equation for the calculation of the period in a spring-masss system

T = \sqrt{\frac{m}{k} }     ( 1 )

- The equation for the velocity of a simple harmonic motion

x = \frac{2\pi }{T}Asin(\frac{2\pi }{T}t)   ( 2 )

where m is the mass of the block, k is the spring constant, A is the amplitude (in this case A = 14 cm) and v is the velocity of the block

Hence

T = \sqrt{\frac{2 kg}{50 N/m}} = 0.2 s

and by reeplacing it in ( 2 ):

v = \frac{2\pi }{0.2s}(14cm)sin(\frac{2\pi }{0.2s}(0.9s)) = 140\pi  sin(9\pi ) = 0

In this case for 0.9 s the velocity is zero, that is, the block is in a position with the max displacement from the equilibrium.

5 0
3 years ago
What is the middle layer of earth called
irinina [24]
The middle or centre of the Earth is the core. However the middle of the layers from the surface to the centre of the Earth is known as mantle. 
6 0
3 years ago
Read 2 more answers
A toy doll and a toy robot are standing on a frictionless surface facing each other. The doll has a mass of 0.2 kg, and the robo
Natali5045456 [20]

Answer:

<h3>1.43m/s²</h3>

Explanation:

According to newtons second law.

F = mass * acceleration

If the doll has a mass of 0.2 kg, and the robot has a mass of 0.5 kg, the resulting mass will be 0.7kg

Force applied = 1N

acceleration = Force/mass

Substitute the values and get acceleration

acceleration = 1/0.7

acceleration = 1.43m/s²

Hence the magnitude of the acceleration of the robot is 1.43m/s²

3 0
3 years ago
Why must you bend forward when carrying a
Arturiano [62]

Answer:

hi I thinks its number 3

Explanation:

hope you have a nice day

5 0
3 years ago
Other questions:
  • What is energy efficiency
    12·1 answer
  • Which of the following is not a unit used to measure pressure?
    10·2 answers
  • Which is the best example of translational motion?
    9·2 answers
  • The Apollo 11 mission was the first mission to land a human on the moon.
    7·1 answer
  • URGENT I WILL GIVE BRAINLIEST
    15·1 answer
  • How long does it take to drive 500 miles at 70 mph?
    7·1 answer
  • Which of the following is a common physical property of ionic compounds? A. high melting point B. insoluble in water C. conduct
    7·2 answers
  • What is the chemical formula for copper (I) sulfide? A) CuS B) CuS2 C) Cu2S D) Cu2S3
    7·2 answers
  • What electric force would a stationary 3.8 C charge experience if it were far away from any other charges
    5·1 answer
  • energy transfered electrically is measured in _____. what one word completes the sentence?give the fullname not symbol.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!