Answer:
9N
Explanation:
static friction=normal force x coefficient of static friction
so static friction =30N x 0.3= 9N
Answer:
h=18.05 cm
Explanation:
Given that
m= 25 kg
K= 1300 N/m
x=26.4 cm
θ= 19.5 ∘
When the block just leave the spring then the speed of block = v m/s
From energy conservation



By putting the values


v=1.9 m/s
When block reach at the maximum height(h) position then the final speed of the block will be zero.
We know that

By putting the values

h=0.1805 m
h=18.05 cm
Answer:
Her speed is 9.8 meter per second
Explanation:
Newton's second law states that acceleration (a) is related with force (F) by:
(1)
Here the only force acting on the firefighter is the weight F=mg so (1) is:
Solving for a:

Now with the acceleration we can use the Galileo's kinematic equation:
(2)
With Vf the final velocity, Vo the initial velocity and Δx the displacement, because the firefighter stars from rest Vo=0 so (2) is:

Solving for Vf


Answer:

Explanation:
F = Force on the sled = 63 N
m = Mass of sled = 28.7 kg
= Coefficient of kinetic friction = 0.169
g = Acceleration due to gravity = 
The force balance of the system is given by

The acceleration of the sled is
.
Answer A
Explanation: because u need to make sure you know the difference between a need and a want