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
Anon25 [30]
4 years ago
12

You throw a baseball (mass 0.145 kg) vertically upward. It leaves your hand moving at 12.0 m/s. Air resistance can be neglected.

At what height above your hand does the ball have (a) half as much upward velocity, (b) half as much kinetic energy as when it left your hand
Physics
1 answer:
Dimas [21]4 years ago
7 0

Answer:

Explanation:

mass of baseball, m = 0.145 kg

initial velocity, u = 12 m/s upward

(a) final velocity, v = u / 2 = 6 m/s

Let the height is h.

Use third equation of motion

v² = u² - 2gh

6 x 6 = 12 x 12 - 2 x 9.8 x h

36 - 144 = - 19.6 x h

h = 5.51 m

(b) initial kinetic energy, K = 0.5 x m x u² = 0.5 x 0.145 x 12 x 12 = 10.44 J

Final kinetic energy, K' = K/2

0.5 x m x v² = 10.44 /2

0.5 x 0.145 x v² = 5.22

v = 8.5 m/s

v² = u² - 2gh

8.5 x 8.5 = 12 x 12 - 2 x 9.8 x h

72.25 - 144 = - 19.6 x h

h = 3.66 m

You might be interested in
All of the following elements produce magnetic fields except for
Bogdan [553]
The correct answer should be D. copper

Nickel, cobalt, and iron, produce magnetic fields when electrified while copper does not.
3 0
3 years ago
Read 2 more answers
An infinite slab of charge of thickness 2z0 lies in the xy-plane between z=−z0 and z=+z0. The volume charge density rho(C/m3) is
Oksi-84 [34.3K]

Answer:

please read the answer below

Explanation:

To find the electric field you can consider the Gaussian law for a cylindrical surface inside the slab.

\int E dA=EA_{G}=\frac{Q_{int}}{\epsilon_o}

Q_{int}=\rho V_{G}

where Qint is the charge inside the Gaussian surface, AG is the area of the surface and rho is the charge density of the slab.

By using the formula for the volume of a cylinder you obtain:

V_{G}=\pi r^2h

where h is the height. If you assume that the slab is in the interval (-zo<z<z0) you can write VG:

V_{G}=\pi r^2 z

Finally, by replacing in the expression for E you get:

E=\frac{Q_{int}}{\epsilon_o A_G}=\frac{Q_{int}}{\epsilon_o \pi r^2}\frac{z}{z}=\frac{\rho z}{\epsilon_o}

E=\rho z/\epsilon_o

hence, for z>0 you obtain E=pz/eo > 0

for z<0 -> E=pz/eo < 0

7 0
3 years ago
A Pitot-static probe is used to measure the speed of an aircraft flying at 3000 m. If the differential pressure reading is 3300
adell [148]

Answer:

   v = 306.76 Km/h

Explanation:

given,

height of the aircraft = 3000 m

differential pressure reading = 3300 N/m²

density of air = 0.909 Kg/m³

speed of aircraft = ?

Assuming the air flowing above air craft is in-compressible, irrotational and steady so, we can use Bernoulli's equation to solve the problem.

using Bernoulli's equation

          \dfrac{v^2}{2} = \dfrac{\Delta P}{\rho}

where ρ is the density of the air at 3000 m

          v= \sqrt{\dfrac{2 \times \Delta P}{\rho}}

          v= \sqrt{\dfrac{2 \times 3300}{0.909}}

          v = \sqrt{7260.726}

                 v = 85.21 m/s

          v= 85.21 \times \dfrac{3600}{1000}

                 v = 306.76 Km/h

4 0
3 years ago
When padding a canoe you push the water backwards with the paddle which in turn will push you forward.which law of motion is bei
iogann1982 [59]

Newton's third law: For every action, there is an opposite and equal reaction.

6 0
3 years ago
Read 2 more answers
How do I do this?<br> Series and parallel circuits.
Svetlanka [38]
Connect the little light thingys to the top of the battery
8 0
3 years ago
Other questions:
  • Why could you hold a stack of books on your head without pain, whereas it would hurt if someone put a small pebble between the b
    5·2 answers
  • A proton traveling to the right enters a region of uniform magnetic field that points into the screen. When the proton enters th
    13·1 answer
  • What is the main difference between the gas water vapor and the liquid water?
    9·2 answers
  • A runner taking part in the 200 m dash must run around the end of a track that has a circular arc with a radius of curvature of
    8·1 answer
  • Suppose astronomers discover a radio message from a civilization whose planet orbits a star 35 light-years away. Their message e
    11·1 answer
  • Ya'll please I need help only on #5 Its confusing<br><br> (Grade 10 Physics, Potential Energy)
    9·1 answer
  • During a gust of wind, the blades of the windmill are given an angular acceleration of α=(0.2 θ) rad/s2, where θ is measured in
    15·1 answer
  • A force of 8,480 N is applied to a cart to accelerate it at a rate of 26.5 m/s2. What is the mass of the cart?
    11·2 answers
  • Alexandra drops an egg from 30 m above the ground to hit Vanessa on the head. If Vanessa stands 3.5 meters tall. How fast is the
    13·1 answer
  • 1. What are Three Things you would build differently if you were to build the rocket again?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!