Answer:

Explanation:
As we know that tension force in the string will be equal to the centripetal force on the string
so we will have

now we have

now we have


now when string length is 0.896 m and its speed is 71.5 m/s then we will have



Answer:
car is moving away its direction is negative.
the speed must also be negative.
speed this distance decreases the acceleration is negative and if the speed is increasing the acceleration is positive.
Explanation:
In the exercise they indicate that the direction to the motion sensor is positive, as they indicate that the car is moving away its direction is negative.
The speed of the car is
v = (x₂-x₁) / t
As the positions are negative, and the car moves away the speed must also be negative.
The analysis for acceleration must be very careful if the speed this distance decreases the acceleration is negative and if the speed is increasing the acceleration is positive.
Answer:
B. 4a
Explanation:
Force between the charges is inversely proportional to the square of the distance
=> Force will be 4 times and acceleration will be 4a
=> Answer b).
Answer:
The spring constant is 215.6 N/m.
Explanation:
Given that,
Distance = 39 cm
Compresses length = 29 cm
Mass = 2.2 kg
We need to calculate the distance
Using formula of distance

Put the value into the formula
We need to calculate the spring constant
Using formula of restoring force


Where, F = force
x = distance
Put the value into the formula


Hence, The spring constant is 215.6 N/m.