Answer:
The velocity of the ball is 0.92 m/s in the downward direction (-0.92 m/s).
Explanation:
Hi there!
The equation for the velocity of an object thrown upward is the following:
v = v0 + g · t
Where:
v = velocity of the ball.
v0 = initial velocity.
g = acceleration due to gravity (-9.8 m/s² considering the upward direction as positive).
t = time.
To find the velocity of the ball at t = 0.40 s, we have to replace "t" by 0.40 s in the equation:
v = v0 + g · t
v = 3.0 m/s - 9.8 m/s² · 0.40 s
v = -0.92 m/s
The velocity of the ball is 0.92 m/s in the downward direction (-0.92 m/s).
Answer:
Of the three stars in the system, the dimmest - called Proxima Centauri - is actually the nearest star to the Sun. The two bright stars, called Alpha Centauri A and B form a close binary system; they are separated by only 23 times the Earth - Sun distance.
Answer:
a) 3.43 m/s
Explanation:
Due to the law of conservation of momentum, the total momentum of the bullet - rifle system must be conserved.
The total momentum before the bullet is shot is zero, because they are both at rest, so:

Instead the total momentum of the system after the shot is:

where:
m = 0.006 kg is the mass of the bullet
M = 1.4 kg is the mass of the rifle
v = 800 m/s is the velocity of the bullet
V is the recoil velocity of the rifle
The total momentum is conserved, therefore we can write:

Which means:

Solving for V, we can find the recoil velocity of the rifle:

where the negative sign indicates that the velocity is opposite to direction of the bullet: so the recoil speed is
a) 3.43 m/s
Answer:
an object sliding down hill
Explanation:
On a slope, the force applied is due to gravity. Its direction is straight down. If the object is sliding down the hill, its displacement is at an angle to the applied force. The angle of displacement will depend on the steepness of the hill.