Answer:
Zero
Explanation:
It is given that,
A person swims to the other end of a 20m long pool and back.
We need to find his displacement.
Displacement = shortest path covered
He reaches at the same position as from where he has started. It means the shortest path covered is equal to 0 i.e. his displacement is zero.
Answer:
Net forces which pushes the window is 30342.78 N.
Explanation:
Given:
Dimension of the office window.
Length of the window = 
m
Width of the window = 
m
Area of the window = 
Difference in air pressure = Inside pressure - Outside pressure
= 
atm = 
atm
Conversion of the pressure in its SI unit.
⇒ 
atm = 
Pa
⇒ atm = 
Pa
We have to find the net force.
We know,
⇒ Pressure = Force/Area
⇒ 
⇒ 
⇒ Plugging the values.
⇒ 
⇒ 
Newton (N)
So,
The net forces which pushes the window is 30342.78 N.
Answer:
14.3kg
Explanation:
Given parameters:
Quantity of heat = 149000J
Change in temperature = 5.23°C
specific heat of the ice = 2000J/kg°C
Unknown:
Mass of the ice in the bag = ?
Solution:
The heat capacity of a substance is given as:
H = m c Ф
H is the heat capacity
m is the mass
c is the specific heat
Ф is the temperature change;
since m is the unknown, we make it the subject of the expression;
m = H/ mФ
m = 
= 14.3kg
Answer:
F = 800N
the magnitude of the average force exerted on the wall by the ball is 800N
Explanation:
Applying the impulse-momentum equation;
Impulse = change in momentum
Ft = m∆v
F = (m∆v)/t
Where;
F = force
t = time
m = mass
∆v = v2 - v1 = change in velocity
Given;
m = 0.80 kg
t = 0.050 s
The ball strikes the wall horizontally with a speed of 25 m/s, and it bounces back with this same speed.
v2 = 25 m/s
v1 = -25 m/s
∆v = v2 - v1 = 25 - (-25) m/s = 25 +25 = 50 m/s
Substituting the values;
F = (m∆v)/t
F = (0.80×50)/0.05
F = 800N
the magnitude of the average force exerted on the wall by the ball is 800N
Answer:
10N to the left side towards you
Explanation:
The net force is the resultant force that acts on a body.
Force is a push or pull on a body.
Push to left side = 25N
Pull to the right = 15N
Net force = Push to left side - Pull to the right = 25N - 15N
Net force = 10N to the left side towards you
The net force is therefore 10N to the left side towards you
