Answer:29.627 m
Explanation:
Given
Initial velocity of life preserver(u) is 1.6 m/s
it takes 2.3 s to reach the water
using equation of motion
v=u+at

v=24.163 m/s
Let s be the height of life preserver



s=29.627 m
Answer:
<h3>0.445</h3>
Explanation:
In friction, the coefficient of friction formula is expressed as;

Ff is the frictional force = Wsinθ
R is the reaction = Wcosθ
Substitute inti the equation;

Given
θ = 24°

Hence the coefficient of kinetic friction between the box and the ramp is 0.445
Answer:
<h2>8.0995×10^-21 kgms^-1</h2>
Explanation:
Mass of proton :

Speed of Proton:

Linear Momentum of a particle having mass (m) and velocity (v) :

Magnitude of momentum :

Frome equation (2), magnitude of linear momentum of the proton :

Given
Weight of the block A, Wa = 20 lb, weight of block B Wb = 50 lb. Applied
force to block A, P = 6lb, coefficient of static friction µs = 0.4, coefficient
of kinetic friction µk = 0.3. If a force P
is applied to the body, no relative motion will take place until the applied
force is equal to the force of friction Ff, which is acting opposite to the
direction of motion. Magnitude of static force of friction between block A and
block B, Fs = µsN, where N is
reaction force acting on block A. Now, resolve the forces Fx = max. P = (mA +
mB)a,
6 = (20 / 32.2 + 50 / 32.2)a
2.173a = 6
A = 2.76 ft/s^2
To check slipping occurs between block A and block B, consider block A:
P – Ff = mAaA
6 – Ff = 1.71
Ff = 4.29 lb
And also,
N = wA. We know static friction,
Fs = µsN
Fs = 0.4 x 20
Fs = 8lb
Frictional force is less than static friction. Ff < Fs
<span>Therefors, acceleration of block A, aA = 2.76 ft/s^2, acceleration of
block B aB = 2.76 ft/s^2</span>