Answer:
2.4 m
Explanation:
Consider the motion along the vertical direction
= initial position of ball above the ground = 4.5 m
= time taken by the ball to hit the smokestack = 0.65 s
= initial velocity of the ball along vertical direction
= acceleration due to gravity = - 9.8 m/s²
= position of ball at the time of hitting the smokestack
Using the kinematics equation

inserting the above values

Answer:
The minimum speed when she leave the ground is 6.10 m/s.
Explanation:
Given that,
Horizontal velocity = 1.4 m/s
Height = 1.8 m
We need to calculate the minimum speed must she leave the ground
Using conservation of energy



Put the value into the formula




Hence, The minimum speed when she leave the ground is 6.10 m/s.
Answer:

Explanation:
We can calculate the acceleration experimented by the passenger using the formula
, taking the initial direction of movement as the positive direction and considering it comes to a rest:

Then we use Newton's 2nd Law to calculate the force the passenger of mass m experimented to have this acceleration:

Which for our values is:

Answer:
the force required to accelerate a 1,100kg car is 550N
Answer:
the boat would be deeped by 3200 m
Explanation:
Given that
The boat arrives back after 4 seconds
And, the speed of the sound in water is 1,600 m/s
We need to find out how much deep is the water
So,
As we know that
Distance = ( speed × time) ÷ 2
Here we divided by 2 because the boat arrives back
= (1600 × 4) ÷ 2
= 3200 m
Therefore the boat would be deeped by 3200 m