If you pull a resistant puppy with its leash in a horizontal direction, it takes 80 N to get it going. You can then keep it moving at constant speed across the floor with a constant, horizontal force of 70 N. The puppy has a weight of 110 N. What is the coefficient of static friction between the puppy and the floor

The coefficient of static friction between the puppy and the floor is 0.7273.

Explanation:

The horizontal force applied to move the puppy from a steady state has to be greater than the force of static friction, after it is moving the force needs to be equal to be greater than the force of dynamic friction in order to maintain its movement. The force of static friction is given by:

Where is the static friction force, is the coefficient of static friction and is the normal force. Since there's no angle on the flor the normal force is equal to the weight of the puppy, therefore, , to make the puppy moving we need to use a force of 80 N, therefore, , so we can solve for the coefficient as shown below:

The coefficient of static friction between the puppy and the floor is 0.7273.

the current is 0.6

voltage ÷ resistance = current

so 12 ÷ 20 = 0.6

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.