The formula for force exerted on/by a spring is
F = k*e where k is the spring constant and x is the distance stretched from
unstrained position. This should allow you to find what you need.
Using F = k x e,
where k is the spring constant,
and e is the extension,
The F is her weight = 45 X 0.80
= 36 N
Answer:
The force is 
Explanation:
From the question we are told that
The mass of the block is 
The coefficient of static friction is 
The coefficient of kinetic friction is 
The normal force acting on the block is

substituting values


Given that the force we are to find is the force required to get the block to start moving then the force acting against this force is the static frictional force which is mathematically evaluated as

substituting values


Now for this block to move the force require is equal to
i.e

=> 
Answer:
The temperature and gravity both affects the density
Answer:
2.35 s
Explanation:
The period of a simple pendulum is expressed as;
T = 2π
Where
T is the period in seconds
L is the length in metres
g is acceleration due to gravity
T = 2π
T = 2.349 s
T = 2.35 s
Organisms that existed over a limited period
Explanation:
Index fossils are organisms that existed within a limited period in the geologic record.
These fossils are indicator fossils that serves as guide to define the relative ages of rocks in a sequence.
Here are some characteristics of index fossils:
- they must have existed over a limited period in their history.
- they must be very distinctive with short evolutionary tend.
- they must be abundant and highly widespread in the stratigraphic column.
Learn more:
Fossils brainly.com/question/7382392
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