The faster car behind is catching up/closing the gap/gaining on 
the slow truck in front at the rate of (90 - 50) = 40 km/hr.
At that rate, it takes (100 m) / (40,000 m/hr) = 1/400 of an hour 
to reach the truck.
(1/400 hour) x (3,600 seconds/hour) = 3600/400 = <em>9 seconds</em>, exactly  
        
                    
             
        
        
        
When we shake a mango tree, the mangoes fall down. It is because when we shake the tree, the mango tend to be rest due to inertia where as the branches are in motion. That is why the mangoes tend to be at rest due to inertia where as the branches are in the motion.
        
             
        
        
        
The period of the pendulum doesn't determine the length of the string.  
It's the other way around.
The period of the pendulum is proportional to the square root of its length.
So if you want to triple the period, you have to make the string nine times 
as long as it is now.
        
             
        
        
        
Answer:
maybe its heat sorry if it's wrong
because if friction is not in the problem so we are making heat or thermal energy 
 
        
             
        
        
        
Answer:
Imp = 25 [kg*m/s]
v₂= 20 [m/s]
Explanation:
In order to solve these problems, we must use the principle of conservation of linear momentum or momentum.
1)

where:
m₁ = mass of the object = 5 [kg]
v₁ = initial velocity = 0 (initially at rest)
F = force = 5 [N]
t = time = 5 [s]
v₂ = velocity after the momentum [m/s]
![(5*0) +(5*5) = (m_{1}*v_{2}) = Imp\\Imp = 25 [kg*m/s]](https://tex.z-dn.net/?f=%285%2A0%29%20%2B%285%2A5%29%20%3D%20%28m_%7B1%7D%2Av_%7B2%7D%29%20%3D%20Imp%5C%5CImp%20%3D%2025%20%5Bkg%2Am%2Fs%5D)
2)
![(m_{1}*v_{1})+(F*t)=(m_{1}*v_{2})\\(0.075*0)+(30*0.05)=(0.075*v_{2})\\v_{2}=20 [m/s]](https://tex.z-dn.net/?f=%28m_%7B1%7D%2Av_%7B1%7D%29%2B%28F%2At%29%3D%28m_%7B1%7D%2Av_%7B2%7D%29%5C%5C%280.075%2A0%29%2B%2830%2A0.05%29%3D%280.075%2Av_%7B2%7D%29%5C%5Cv_%7B2%7D%3D20%20%5Bm%2Fs%5D)