.a car increases its speed from 10 m/s to 20/s in 2.5. seconds calculate it’s acceleration
1 answer:
Answer:
Explanation:
Acceleration is the rate of change of an object with respect to time. It is the change in velocity over the time.
The car starts at 10 meters per second and increases to 20 meters per second in 2.5 seconds.
= 20 m/s
= 10 m/s
- t= 2.5 s
Substitute the values into the formula.
Solve the numerator.
Divide.
The acceleration of the car is <u>4 meters per second squared.</u>
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The initial kinetic energy of the cart is
(1)
where m is the mass of the cart and v its initial velocity.
Then, the cart hits the spring compressing it. The maximum compression occurs when the cart stops, and at that point the kinetic energy of the cart is zero, so all its initial kinetic energy has been converted into elastic potential energy of the spring:
where k is the spring constant and x is the spring compression.
For energy conservation, K=U. We can calculate U first: the compression of the spring is x=60 cm=0.60 m, while the spring constant is k=250 N/m, so
So, the initial kinetic energy of the cart is also 45 J, and from (1) we can find the value of the initial velocity:
where m is the mass of the cart and v its initial velocity.
Then, the cart hits the spring compressing it. The maximum compression occurs when the cart stops, and at that point the kinetic energy of the cart is zero, so all its initial kinetic energy has been converted into elastic potential energy of the spring:
where k is the spring constant and x is the spring compression.
For energy conservation, K=U. We can calculate U first: the compression of the spring is x=60 cm=0.60 m, while the spring constant is k=250 N/m, so
So, the initial kinetic energy of the cart is also 45 J, and from (1) we can find the value of the initial velocity: