Answer:
1.71
Explanation:
the parabolic movment is described by the following equation:

where y is the height of the ball, a is the angle of launch,
the initial velocity, g the gravity and x is the horizontal distance of the ball.
So, if we want that the ball reach the hood, we will replace values on the equation as:

Finally, solving for
, we get:

1.71
Answer: Work done by the box will be 8 Joules.
Explanation:
Work done by a substance is the product of the force applied on it and the displacement of a substance.
Mathematically,

Where,
W = work done = ? J
F = Force applied = 4 N
s = displacement = 2 m
Putting values in above equation, we get:

Hence, work done by the box will be 8 Joules.
Answer:
Work done is zero
Explanation:
given data
Angle of kite with horizontal = 30 degree
tension in the string = 4.5 N
WE KNOW THAT
Work = force * distance
horizontal force = 
DISTANCE = 0 as boy stands still. therefore
work done = 3.89 *0 = 0
A: makes work easier to do.
Answer:
negative acceleration of 4m/s²
Explanation:
Given parameters:
Initial velocity = 66m/s
Final velocity = 26m/s
Time taken = 10s
Unknown:
Description of the acceleration = ?
Solution:
Acceleration is the rate of change of velocity with time.
It is mathematically expressed as;
acceleration =
v is the final velocity
u is the initial velocity
t is the time taken
Now insert the parameters and solve;
Acceleration =
= -4m/s²
So, we see a negative acceleration of 4m/s²