Answer:
No acceleration.
Explanation:
If the forces are Balanced it means they are in equilibrium and there will be no net force, therefore the object will not accelerate and the velocity will remain constant.
A water pipe freezes and cracks on a cold night. <em> (D)</em>
There are three physical changes going on in this scenario:
1). The air gets cold and dark at night.
2). The water in the pipe freezes and expands.
3). The pipe cracks.
There are no chemical changes in the description.
Answer:
Explanation:
a ) Height to be cleared = 5 - 1.6 = 3.4 m
Horizontal distance to be cleared = 5 m .
angle of throw = 56°
here y = 3.4 , x = 5 , θ = 56
equation of trajectory
y = x tanθ - 1/2 g ( x/ucosθ)²
3.4 = 5 tan56 - 1/2 g ( 5/ucos56)²
3.4 = 7.4 - 122.5 / .3125u²
122.5 / .3125u² = 4
u² = 98
u = 9.9 m /s
Range = u² sin 2 x 56 / g
= 9.9 x 9.9 x .927 / 9.8
= 9.27 m
horizontal distance be-yond the fence will the rock land on the ground
= 9.27 - 5
= 4.27 m
Answer:
Cannonball b spends more time in the air than cannonball a.
Explanation:
Starting with the definition of acceleration, we have that:

Since both cannonballs will stop in their maximum height, their final velocity is zero. And since the acceleration in the y-axis is g, we have:

Now, this time interval is from the moment the cannonballs are launched to the moment of their maximum height, exactly the half of their time in the air. So their flying time t_f is (the minus sign is ignored since we are interested in the magnitudes only):

Then, we can see that the time the cannonballs spend in the air is proportional to the vertical component of the initial velocity. And we know that:

Finally, since
and
, we can conclude that:

In words, the cannonball b spends more time in the air than cannonball a.