Answer:
9 cm.
Explanation:
The energy used for stretch the spring from 
to 
will be , 
The energy used for stretch the spring from to 
will be , 
using the energy of spring formula ,we find that
Dividing both the equation will get,
Therefore, the natural length of the spring is, 9 cm.
Answer:
Cheetah cubs are in danger from predators like lions and hyenas which can track their prey by scent and so the mother and her cubs leave an area when their scent is too strong so that they are not hunted and the cubs survive.
Mother Cheetahs also train their cubs to hunt so that they may get food for themselves which will ensure their survival as well thus showing that both of these practices can impact on reproductive success.
C. element only one substance
Answer:
At the end points of motion (either side) the velocity must be zero because the velocity is changing from - to + (it can't turn around around without passing thru zero,
The velocity will then increase to the midpoint of the motion.
m g h = 1/2 m v^2 where h is the vertical distance thru which the pendulum travels
Answer: The net force acting on the car 1,299.3 N.
Explanation:
Mass of the car = 710 kg
Initial velocity of the car of the ,u= 37 km/h= 10.27 m/s 
Final velocity of the car,v = 120 km/h = 33.33 m/s
time taken b y car = 12.6 sec
v-u=at
The net force acting on the car 1,299.3 N.
