Answer:
Therefore, the situation in which both the instantaneous velocity and acceleration become zero, is the situation when the ball reaches the highest point of its motion.
Explanation:
When a ball is thrown upward under the free fall action of gravity, it starts to loose its Kinetic Energy as it moves upward. As the ball moves in upward direction, its kinetic energy gradually converts into its potential energy. As a result the speed of the ball starts to decrease as it moves up. Therefore, at the highest point during its motion, the velocity of ball becomes zero and it stops at the highest point for a moment, and then it starts to fall back down, under the influence of gravitational force.
Therefore, the situation in which both the instantaneous velocity and acceleration become zero, is the situation <u>when the ball reaches the highest point of its motion.</u>
Answer:
The girl exerts more pressure.
Explanation:
Pressure can be defined as the force exerted normally or perpendicularly per unit area.
i.e P = F/A
<u>Girls</u>
Area of the heel = 1cm² = 10^(-4) m²
Force = mg = 50 × 10 = 500N
Pressure =


<u>Elephant</u>
<u>Area</u><u> </u><u>=</u><u> </u><u>2</u><u>5</u><u>0</u><u>cm</u><u>²</u><u> </u><u>=</u><u> </u><u>2</u><u>.</u><u>5</u><u> </u><u>x</u><u> </u><u>1</u><u>0</u><u>^</u><u>(</u><u>-</u><u>2</u><u>)</u><u>b</u><u> </u><u>m</u><u>²</u>
<u>Force</u><u> </u><u>=</u><u> </u><u>mg</u><u> </u><u>=</u><u> </u><u>4</u><u>0</u><u>0</u><u>0</u><u>0</u><u>N</u>
<u>Pressure</u><u> </u><u>=</u><u> </u>
<u>
</u>
<u>
</u>
Answer:
F= 0
Explanation:
This exercise we use Newton's second law,
F = m a
in this case as the speed is constant the acceleration is zero therefore the force is zero.
Change we can solve it using Newton's first law, which states that every vehicle remains still or with constant speed if there is no extensive outside acting on it
We see that with any of the two forms the sum of the applied forces is zero
∑ F = 0
Answer:
<em>The velocity of the two cars is 10 m/s after the collision.</em>
Explanation:
<u>Law Of Conservation Of Linear Momentum
</u>
The total momentum of a system of bodies is conserved unless an external force is applied to it. The formula for the momentum of a body with mass m and velocity v is
P=m.v
If we have a system of bodies, then the total momentum is the sum of them all

If some collision occurs, the velocities change to v' and the final momentum is:

In a system of two masses, the law of conservation of linear momentum takes the form:

If both masses stick together after the collision at a common speed v', then:

The car of mass m1=1000 Kg travels at v1=25 m/s and collides with another car of m2=1500 Kg which is at rest (v2=0).
Knowing both cars stick and move together after the collision, their velocity is found solving for v':



v' = 10 m/s
The velocity of the two cars is 10 m/s after the collision.
Answer : The correct option is, (D) 273 Kelvin, 0 degrees Celsius, 32 degrees Fahrenheit
Explanation :
Conversion of degree Celsius to Kelvin :

Conversion of degree Celsius to degrees Fahrenheit :

By using these two conversion factors, we get the three temperature readings all mean the same thing.
For option A :


For option B :


For option C :


For option D :


From the given options, only option (D) is correct.
Hence, the correct option is, (D) 273 Kelvin, 0 degrees Celsius, 32 degrees Fahrenheit