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
Harrizon [31]
4 years ago
12

Can someone help me?!!!!!

Physics
1 answer:
Serga [27]4 years ago
7 0

Answer:

33 m/s

Explanation:

By analyzing the vertical motion, we can find what is the time of flight of the projectile. The vertical position is

y(t) = h + v_{0y}t - \frac{1}{2}gt^2

where

h = 20 m is the initial height

v_{0y} = 26 m/s is the initial vertical velocity

g=9.8 m/s^2 is the acceleration due to gravity

By putting y(t)=0, we find the time t at which the projectile hits the ground:

0=20 + 26 t - 4.9t^2

which has 2 solutions:

t = -0.7 s

t = 6.0 s

We discard the negative solution since it has no physical meaning. So, we know that the projectile hits the ground 6.0 s later after the launch.

The vertical velocity is given by

v_y (t)= v_{0y} -gt

So we can find the vertical velocity when the projectile reaches point Q, by substituting t=6.0 s into this equation:

v_y = 26 m/s - (9.8 m/s^2)(6.0 s)=-32.8 m/s \sim -33 m/s

and the negative sign means the direction is downward.

You might be interested in
Electrical wire with a diameter of .5 cm is wound on a spool with a radius of 30 cm and a height of 24 cm.
kow [346]

Answer:

a)   # lap = 301.59 rad , b)   L = 90.48 m

Explanation:

a) Let's use a direct proportions rule (rule of three). If one turn of the wire covers 0.05 cm, how many turns do you need to cover 24 cm

          # turns = 1 turn (24 cm / 0.5 cm)

         # laps = 48 laps

Let's reduce to radians

        # laps = 48 laps (2 round / 1 round)

       # lap = 301.59 rad

b) Each lap gives a length equal to the length of the circle

          L₀ = 2π R

          L = # turns L₀

          L = # turns 2π R

          L = 48 2π 30

          L = 9047.79 cm

          L = 90.48 m

6 0
4 years ago
A beaker has a mass of 125g. What is the mass of this beaker in decigrams
Anit [1.1K]
1250 decigrams
1 gram = 10 decigrams
4 0
4 years ago
Consider as a system the Sun with Saturn in a circular orbit around it. Find the magnitude of the change in the velocity of the
Doss [256]

Answer:

v_{su} = 19.44 m/s

Explanation:

m_{su}=5.68x10^{29}kg\\m_{sa}=5.68x10^{26}kg

T=9.29x10^8\\r_{o}=1.43x10^{12}

If the sun considered as x=0 on the axis to put the center of the mass as a:

m_{su}*r_{o}=(m_{sa}+m_{su})*r_{1}

solve to r1

r_1=\frac{m_{sa}*r_{o}}{m_{sa}+m_{su}}=\frac{5.68x10^{26}*1.43x10^{12}}{5.68x10^{26}+5.68x10^{26}}

r_1=1.428x10^9m

Now convert to coordinates centered on the center of mass.  call the new coordinates x' and y' (we won't need y').  Now since in the sun centered coordinates the angular momentum was  

L = \frac{m_{sa}*2*pi*r_1^2}{T}

where T = orbital period

then L'(x',y') = L(x) by conservation of angular momentum.  So that means

L_{sun}=\frac{m_{sa}*2*\pi *( 2r_{o}*r_1 -r_1^2)}{T}

Since

L_{su}= m_{su}*v_{su}*r_1

then

v_{su}=\frac{m_{sa}*2*pi*(2r_{o}*r_{1}-r_{1}^2)}{T*m_{sa}*r_1}

v_{su} = 19.44 m/s

7 0
4 years ago
A fruit bat falls from the roof of a cave. We know that her potential energy was
bulgar [2K]

Answer:

v = 15.65 m/s

Explanation:

We use conservation of mechanical energy between initial (i) and final (f) states:

Pi + KEi = Pf + KEf

At the top of the cave at the instant the bat starts to fall, there is only potential energy since the bat's velocity is zero.

Pi = m g h = 600 J

and the KEi = 0 J (no velocity)

Knowing the height of the cave's roof (12.8 m) , we can find the mass of the bat:

m = 600 J / (g 12.5) = 4.9 kg

Using conservation of mechanical energy, the final state is:

Pf + KEf = 600 J

with Pf = 0 (just touching the ground)

KEf= 1/2  4.9 (v^2)

and we solve for the velocity:

600 J = 0 + 1/2  4.9 (v^2)

v^2 = 600 * 2 / 4.9 = 244.9

v = 15.65 m/s

5 0
3 years ago
A teacher asks her students to jump off of the ground. Once the students complete the task, she says, "All of you just made Eart
Crazy boy [7]

Answer:

Explained below

Explanation:

A) Newton's first law of motion states that an object will remain at rest or continue in its current state of motion except it is acted upon by another force.

Now using this law, when you jump off the ground, the earth will move a tiny bit and accelerate due to the force applied by the jumping.

B) Newton's 2nd law states that the acceleration of a system is directly proportional to the net external force acting on that system, is in the same direction with it and also inversely proportional to the mass.

In this case, when one jumps, an external force is exerted on the earth and we are told it is directly proportional to the acceleration of the system which in this case it's the earth, then it means that there is some motion by the earth even though you didn't see it move.

C) Newton's third law of motion states that to every action, there is an equal and opposite reaction.

In this case the motion of the jumper will lead to an equal and opposite reaction of the earth.

8 0
3 years ago
Other questions:
  • Which statement correctly describes the differences between positive and negative acceleration? Positive acceleration describes
    13·2 answers
  • Cathode rays were shown to be a stream of _____.
    6·2 answers
  • ) A 1000-kg car is moving at 30 m/s around a horizontal unbanked curve whose diameter is 0.20 km. What is the magnitude of the f
    9·1 answer
  • The two hot-air balloons in the drawing are 48.2 and 61.0 m above the ground. A person in the left balloon observes that the rig
    14·1 answer
  • I’m carbon cycle, CO2 is mainly stored in
    14·1 answer
  • Define very long base line interferometry
    8·2 answers
  • State whether the light from an object moving towards us will be red shifted or blue shifted and explain why.
    12·1 answer
  • A car has a mass of 1000 kg and a momentum of 12 000 kg m / s.<br> What is its kinetic energy?
    7·1 answer
  • HELP ME ASAP PLS, ( zoom in on the picture )
    13·1 answer
  • The aim of the newton's first law experiment ​
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!