Complete Question 
An airplane takes off a runway at a constant speed of 49 m/s at constant angle 30 to the horizontal.How high (in meters )  is the airplane above the ground 13 seconds after takeoff?
Answer:
The height  is 
Explanation:
From the question we are told that 
    The speed at which the plane takes off is  
       The angle at which it takes off is  
         The time taken is 
The vertical distance traveled is  mathematically represented as
           
Substituting values   
          
         
 
        
             
        
        
        
Answer:
-20000 kgm/s
Explanation:
Impulse: This can be defined as the product of the mass of a body and its change in velocity. The S.I unit of impulse is kgm/s.
Mathematically, impulse can be expressed as
I = m(v-u).............. Equation 1.
Where I = impulse applied to the car to bring it to rest, m = mass of the car, u = initial velocity of the car, v = final velocity of the car.
Given: m = 1000 kg, u = 20 m/s, v = 0 m/s ( to rest)
Substitute into equation 1
I = 100(0-20)
I = 1000(-20)
I = -20000 kgm/s
Hence the impulse applied to the car to bring it to rest = -20000 kgm/s
 
        
             
        
        
        
Answer:
The mass of the products and reactants are the same on both sides of the equation. 
The number of atoms of products and reactants are equal and hence it proves the law of conservation of mass.
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The minimum speed of the water must be 3.4 m/s
Explanation:
There are two forces acting on the water in the pail when it is at the top of its circular motion:
- The force of gravity, mg, acting downward (where m is the mass of the water and g the acceleration of gravity)
- The normal reaction, N also acting downward
Since the water is in circular motion, the net force must be equal to the centripetal force, so:

Where:

v is the speed of the pail
r = 1.2 m is the radius of the circle
The water starts to spill out when the normal reaction of the pail becomes zero:
N = 0
When this occurs, the equation becomes:

And substitutin the values of g and r, we find the minimum speed that the water must have in order not to spill out:

Learn more about circular motion:
brainly.com/question/2562955
brainly.com/question/6372960
#LearnwithBrainly
 
        
             
        
        
        
Linear expansivity is a type of thermal expansion. It is described by a fraction that represents the fractional increase in length of a thin beam of a material exposed to a temperature increase of one degree Celsius. ... Linear expansivity is used in many real world applications.