Answer: a = 1.32m/s2
Therefore, the average acceleration is 1.32m/s2
Explanation:
Acceleration is the rate of change in the velocity per time
a = change in velocity/time
a = ∆v/t
average acceleration a = (v2 -v1)/t. ....1
Given;
Final velocity v2 = 1.63m/s
Initial velocity v1 = -1.15ms
time taken t = 2.11s
Substituting into eqn 1
a = [1.63 - (-1.15)]/2.11
a = (1.63+1.15)/2.11
a = 2.78/2.11
a = 1.32m/s2
Therefore, the average acceleration is 1.32m/s2
 
        
             
        
        
        
Answer:
(B) 13.9 m
(C) 1.06 s
Explanation:
Given:
v₀ = 5.2 m/s
y₀ = 12.5 m
(A) The acceleration in free fall is -9.8 m/s².
(B) At maximum height, v = 0 m/s.
v² = v₀² + 2aΔy
(0 m/s)² = (5.2 m/s)² + 2 (-9.8 m/s²) (y − 12.5 m)
y = 13.9 m
(C) When the shell returns to a height of 12.5 m, the final velocity v is -5.2 m/s.
v = at + v₀
-5.2 m/s = (-9.8 m/s²) t + 5.2 m/s
t = 1.06 s
 
        
             
        
        
        
The initial velocity of the ball is 1.01 m/s
Explanation:
The motion of the ball rolling off the desk is a projectile motion, which consists of two independent motions:
- A uniform horizontal motion with constant horizontal velocity
- A vertical accelerated motion with constant acceleration ( , acceleration due to gravity)
, acceleration due to gravity)
We start by analyzing the vertical motion: we can find the time of flight of the ball by using the following suvat equation

where
s = 1.20 m is the vertical displacement (the height of the desk)
u = 0 is the initial vertical velocity

t is the time of flight
Solving for t,

Now we analyze the horizontal motion. We know that the ball covers a horizontal distance of
d = 0.50 m
in a time 
t = 0.495 s
Therefore, since the horizontal velocity is constant, we can calculate it as

So, the ball rolls off the table at 1.01 m/s.
Learn more about projectile motion:
brainly.com/question/8751410
#LearnwithBrainly
 
        
             
        
        
        
Answer:
The cooling time will not be reduced.
Explanation:
The time to cook is virtually the same in both types, vigorously and gently boiling water. 
The reason cooking of spaghetti  calls for vigorously boiling water is to keep the pasta agitated so that they do not stick to one another.
The temperature of boiling water is the same for both vigorously boiling water and gently boiling water, therefore there will be little time difference in when the potatoes will cook when it is done with vigorously boiling water than when it is cooked with gently boiling water.
However cooking potatoes in vigorously boiling water may cause the water to dry up on time and the potatoes get burnt.
 
        
             
        
        
        
Power is the rate of energy. Mathematically, it is
Power (p) = Energy(E) / Time(t)
Hope this helps!