<span>3.92 m/s^2
Assuming that the local gravitational acceleration is 9.8 m/s^2, then the maximum acceleration that the truck can have is the coefficient of static friction multiplied by the local gravitational acceleration, so
0.4 * 9.8 m/s^2 = 3.92 m/s^2
If you want the more complicated answer, the normal force that the crate exerts is it's mass times the local gravitational acceleration, so
20.0 kg * 9.8 m/s^2 = 196 kg*m/s^2 = 196 N
Multiply by the coefficient of static friction, giving
196 N * 0.4 = 78.4 N
So we need to apply 78.4 N of force to start the crate moving. Let's divide by the crate's mass
78.4 N / 20.0 kg
= 78.4 kg*m/s^2 / 20.0 kg
= 3.92 m/s^2
And you get the same result.</span>
The velocity of the ball when it reaches the ground is equal to B. 68.6 m/s. This value was obtained from the formula Vf = Vi + at. Vf is the final velocity. Vi is the initial velocity. The acceleration is "a", while the time of travel is "t". The solution is:
<span>Vf = Vi + at
</span>Vf = 0 + (-9.8 m/s^2) (7 s)
Vf = -68.6 m/s
The negative sign denotes the direction of the ball.
By using Displacement method we can find volume of irregular object like marble.
<h3>What is
displacement method?</h3>
In displacement method,
First , we measuring the volume of water displaced by an object which tell us the volume of the object.
Secondly We can use the physical balance to determine its mass.
Lastly , calculate the density by dividing the mass by the volume.
Procedure to find the Volume of irregular object i.e. marble
step 1 - Fill the graduated cylinder about half full and measure the initial volume of water.
step 2 - Drop the marble in the graduated cylinder.
step 3 -Now measure the final level of water.
Step 4 - Subtract both the values.
Here , comes the Volume of Irregular Object.
For more volume related question visit here:
brainly.com/question/1578538
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It is an example of rolling friction because balls roll.
Answer is ROLLING
Answer:
a. one-half as great
Explanation:
The power developed by the first lifter is one-half as great as that of the second person.
Power is defined as the rate at which work is done;
Power = 
Since the two lifters do the same work at different time, let us estimate their power;
P₁ = 
P₂ = 
We see that for P₁, power is half of the work done whereas in P₂ power is the same as the work done.
Therefore,
The power of the first weight lifter is one-half the second lifter.
