A 1.5 kg ball pushed with a force of 13.5 N accelerates to the left. What is the acceleration of the ball?

A car moves in a straight line at a speed of 68.5 km/h. How far (in km) will the car move in 5.45 minutes at this speed?

AlekseyPX

If you divide 68.5 km/h by 60 (the minutes in an hour) and then you get 1.141 then you multiply it by 5.45 and you get 6.222!

Your Answer is 6.222!!!!

5 0

2 years ago

A ball, with a mass of 5.9kg, is thrown directly upwards. It reaches a maximum height of 10m from the point at which it was rele

katrin2010 [14]

Answer:

14 m/s

Explanation:

We can solve the problem by using the law of conservation of energy.

At the beginning, when the ball is thrown from the ground, it has only kinetic energy, which is given by

$K=\frac{1}{2}mv^2$

where m = 5.9 kg is the mass of the ball and v is its initial speed.

As the ball goes up, its speed decreases, so its kinetic energy decreases and converts into gravitational potential energy. When the ball reaches its maximum height, the speed has become zero, and all the kinetic energy has been converted into gravitational potential energy, given by:

$U=mgh$

where g = 9.8 m/s^2 is the gravitational acceleration and h = 10 m is the maximum height reached by the ball.

Since we can ignore air resistance, energy must be conserved, so the initial kinetic energy must be equal to the final potential energy of the ball, so we can write:

$K=U\\\frac{1}{2}mv^2=mgh$

And we can solve the equation to find v, the initial speed of the ball:

$v=\sqrt{2gh}=\sqrt{2(9.8 m/s^2)(10 m)}=14 m/s$

8 0

2 years ago

15. A volleyball player who weighs 650 Newtons jumps 0.500 meters vertically off the floor. What is her kinetic energy just befo

allochka39001 [22]

<h2>Kinetic energy just before hitting the floor is 324.57 J</h2>

Explanation:

Weight of volleyball player = 650 N

That is

Mass x Acceleration due to gravity = 650

Mass x 9.81 = 650

Mass = 66.26 kg

We also have equation of motion v² = u² + 2as

Initial velocity, u = 0 m/s

Acceleration, a = 9.81 m/s²

Final velocity, v = ?

Displacement, s = 0.5 m

Substituting

v² = u² + 2as

v² = 0² + 2 x 9.81 x 0.5

v = 3.13 m/s

Velocity with which he lands on ground is 3.13 m/s

We have kinetic energy = 0.5 x Mass x Velocity²

Substituting

Kinetic energy = 0.5 x 66.26 x 3.13²

Kinetic energy = 324.57 J

Kinetic energy just before hitting the floor is 324.57 J

3 0

2 years ago

Singing that is off-pitch by more than about 1% sounds bad. How fast would a singer have to be moving relative to the rest of a

Nina [5.8K]

Answer:

-3.396 m/s or 3.465 m/s

Explanation:

v = Speed of sound in air = 343 m/s

$v_s$ = Relative speed of the singer

f = Observed frequency

f' = Actual frequency

1% change can mean $f=1.01f'$

From the Doppler effect equation we have

$f=f'\dfrac{v}{v+v_s}\\\Rightarrow 1.01f'=f'\dfrac{v}{v+v_s}\\\Rightarrow 1.01=\dfrac{343}{343+v_s}\\\Rightarrow v_s=\dfrac{343}{1.01}-343\\\Rightarrow v_s=-3.396\ m/s$

The velocity is -3.396 m/s

when $f=0.99f'$

$f=f'\dfrac{v}{v+v_s}\\\Rightarrow 0.99f'=f'\dfrac{v}{v+v_s}\\\Rightarrow 0.99=\dfrac{343}{343+v_s}\\\Rightarrow v_s=\dfrac{343}{0.99}-343\\\Rightarrow v_s=3.46464646465\ m/s$

The velocity is 3.465 m/s

3 0

2 years ago

Hai ô tô khởi hành cùng lúc từ A,B cách nhau 20 km chuyển động theo hướng từ A đến B vs vận tốc lần lượt là 60km/h và 40km/h

sdas [7]

Answer:

áp dụng công thức v = s/t

s là dộ dài qduong

v là vận tốc

t là thời gian

xuyên suốt 2 câu hỏi đều dùng công thức này

Explanation:

6 0

1 year ago

A 1.5 kg ball pushed with a force of 13.5 N accelerates to the left. What is the acceleration of the ball?​

A 1.5 kg ball pushed with a force of 13.5 N accelerates to the left. What is the acceleration of the ball?