Physics, 14.09.2019 01:30 Kaesy24

Astudent at the top of a building of height h throws ball a straight upward with speed v0 (3 m/s) and throws ball b straight downward with the same initial speed. a. compare the balls’ accelerations, both direction, and magnitude, immediately after they leave her hand. is one acceleration larger than the other? or are the magnitudes equal? b. compare the final speeds of the balls as they reach the ground. is one larger than the other? or are they equal?

Answers: 1

Show answers

Answers

The magnitude of the acceleration of both balls immediately after they left her hand is the same but the direction is different.

The velocity of the ball thrown upwards will be larger than the velocity of the ball thrown downwards when they reach the ground.

The given parameters;

height of the building = hinitial velocity of the ball A = v₀initial velocity of the ball B, = v₀

Both balls experiences acceleration due to gravity, given in the following equation;

$h_{up} = v_ot - \frac{1}{2} gt^2\\\\h_{down} = v_0t + \frac{1}{2} gt^2$

Thus, the magnitude of the acceleration of both balls immediately after they left her hand is the same but the direction is different.

The final velocity of the ball dropped downwards is calculated as;

$v_f^2 = v_0 + 2gh\\\\v_f = \sqrt{v_0 + 2gh}$

The maximum height reached by the ball projected upwards is calculated as follows;

$h_o = v_0 - \frac{1}{2} gt^2$

The final velocity of the ball thrown upwards before it hits the ground;

$v_f^2 = v_0 ^2 + 2gh\\\\v_f^2 = 0 + 2g(h_0 + h)\\\\v_f^2 = 2gh + 2gh_0\\\\v_f^2 = 2gh + 2g(v_0 - \frac{1}{2} gt^2)\\\\v_f^2 = 2gh + 2gv_0 - g^2t^2\\\\v_f = \sqrt{ 2gh + 2gv_0 - g^2t^2$

Thus, the velocity of the ball thrown upwards will be larger than the velocity of the ball thrown downwards when they reach the ground. The direction of both velocities is the same when they reach the ground.

Learn more here:link

Answer from: nina4552

same

Explanation:

Given

ball A initial velocity=3 m/s(upward)

Ball B initial velocity=3 m/s (downward)

Acceleration on both the balls will be acceleration due to gravity which will be downward in direction

Both acceleration is equal

For ball A

maximum height reached is $h_1=\frac{3^2}{2g}$

After that it starts to move downwards

thus ball have to travel a distance of h_1+h(building height)

so ball A final velocity when it reaches the ground is

$v_a^2=2g\left ( h_1+h\right )$

$v_a^2=2g\left ( 0.458+h\right )$

$v_a=\sqrt{2g\left ( 0.458+h\right )}$

For ball b

$v_b^2-\left ( 3\right )^2=2g\left ( h\right )$

$v_b^2=2g\left ( \frac{3^2}{2g}+h\right )$

$v_b=\sqrt{2g\left ( 0.458+h\right )}$

thus v_a=v_b

Answer from: Quest

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.

Answer from: Quest

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol

b. a hockey puck sliding across the ice

c. a compressed spring

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice is the correct option.

Another question on Physics

Physics, 22.06.2019 10:30

Astone weighing 1.5 kilograms is resting on a rock at a height of 20 meters above the ground. the stone rolls down 10 meters and comes to rest on a patch of moss. the gravitational potential energy of the stone on the moss is joules.

Answers: 1

Answer

Physics, 22.06.2019 11:00

Marcella is a four-year-old girl who is a victim of emotional child abuse. based on the child and family services improvement and innovation act of 2011, which action should the government take for marcella? a. the state should arrest marcella’s abuser. b. the state should find a home for marcella as soon as possible. c. the state should enforce stricter laws in the area where marcella resides. d. the state should provide medical assistance to marcella.

Answers: 3

Answer

Physics, 22.06.2019 15:30

1kg of water needs to recieve 4200j of energy to go from 90 degrees to 91 degrees. what is the specific heat capacity of water? what are the units?

Answers: 1

Answer

Physics, 22.06.2019 19:50

An electron moves with a constant horizontal velocity of 3.0 × 106 m/s and no initial vertical velocity as it enters a deflector inside a tv tube. the electron strikes the screen after traveling 26 cm horizontally and 19 cm vertically upward with no horizontal acceleration. what is the constant vertical acceleration provided by the deflector? (the effects of gravity can be ignored.)

Answers: 2

Answer

You know the right answer?

Astudent at the top of a building of height h throws ball a straight upward with speed v0 (3 m/s) an...

Questions