Answer:
The speed with which the baseball leaves the hand = 20.58 m/s
Explanation:
The time take to reach highest height during a projectile's flight is given by
t = (u sin θ)/g
u = initial velocity of the baseball = ?
θ = angle of throw above the horizontal
g = acceleration due to gravity = 9.8 m/s²
1.05 = (u sin 30)/9.8
u = (1.05 × 9.8)/0.5
u = 20.58 m/s
This question deals with the law of conservation of momentum, which basically says that the total momentum in a system must stay the same, provided there are no outside forces. Since you were given the mass and velocity of the two objects you can find the momentum (p=mv) of each and then add them together to find the total momentum of the system before they collide. This total momentum must be the same after they collide. Since you have the mass and velocity of one of the objects after the collision you can find the its momentum after. Subtract this from the the system total and you will have the momentum of the other object after the collision. Now that you know the momentum of the other object you can find its velocity using p=mv and its mass from before.
Be careful with the velocities. They are vectors, so direction matters. Typically moving to the right is positive (+) and moving to the left is negative (-). It is not clear from your question which direction the objects are moving before and after the collision.
Answer:
No, the velocity of the grocery cart will not remain constant, but instead will increase continuously
Explanation:
No the grocery cart will not move at constant velocity over the spilled maragine because as the frictional force is changed to - 20 N, the net force will not be equal to zero
Net force on the cart when frictional force is changed to - 20 N is 40 - 20 N = 20 N
As the force is positive, it means that the force is acting in the direction of motion of the cart and will increase the velocity of the cart as the force is acting in the direction of motion
∴ The velocity of the cart will not remain constant instead it will increase
The average speed can be easily calculated by taking the
ratio of distance and time. That is:
average speed = distance / time
so calculating:
average speed = 4875 ft / 6.85 minutes
<span>average speed = 711.68 ft / min</span>
