Answer:
<h2>15.25 N</h2>
Explanation:
A force of 
is acting on a wagon along the road. The wagon weights 
. Acceleration of the wagon is given as 
.
Consider the block as the system, the forces acting are Frictional force, Gravitational force, Normal reaction and External force applied by us.
Gravitational Force and Normal Reaction cancel out each other.
Net External Force = Mass of system/wagon 
Acceleration of wagon
has a negative sign because it opposes the motion of the wagon.
∴ Frictional Force = 15.25 N
Answer
given,
mass of the person, m = 50 Kg
length of scaffold = 6 m
mass of scaffold, M= 70 Kg
distance of person standing from one end = 1.5 m
Tension in the vertical rope = ?
now equating all the vertical forces acting in the system.
T₁ + T₂ = m g + M g
T₁ + T₂ = 50 x 9.8 + 70 x 9.8
T₁ + T₂ = 1176...........(1)
system is equilibrium so, the moment along the system will also be zero.
taking moment about rope with tension T₂.
now,
T₁ x 6 - mg x (6-1.5) - M g x 3 = 0
'3 m' is used because the weight of the scaffold pass through center of gravity.
6 T₁ = 50 x 9.8 x 4.5 + 70 x 9.8 x 3
6 T₁ = 4263
T₁ = 710.5 N
from equation (1)
T₂ = 1176 - 710.5
T₂ = 465.5 N
hence, T₁ = 710.5 N and T₂ = 465.5 N
Answer:
831.4 J
Explanation:
Info given:
mass adult: 82.5kg
mass child: 14.7kg
height of wall: 1.25m
g = 9.81m/s^2
PE = mgh
For adult:
mgh = (82.5kg)(9.81m/s^2)(1.25m) = 1011.65 J
For child:
mgh = (14.7kg)(9.81m/s^2)(1.25m) = 180.25 J
Difference in PE: 1011.65 J - 180.25 J = 831.4 J
Answer:
The density of plastic is equal to 0.6 g/mL.
Explanation:
Given that,
The mass of piece of plastic, m = 15 g
It is placed in a graduated cylinder. The water level in the graduated cylinder rises from 30 mL to 55 mL when the plastic is added.
We need to find the density of plastic.
Rise in volume = 55 mL - 30 mL
= 25 mL
The density of an object is given by :
So, the density of plastic is equal to 0.6 g/mL.
Answer:
the total cross-sectional area of the capillaries is greater than the total cross-sectional area of the arteries or any other part of the circulatory system.
Explanation:
Blood velocity is not the same in all areas. In the capillaries it is where there is less speed, while in arteries and veins it is quite similar. This is due to the cross-sectional area of each of the vessels. It is a mistake to think of a vein, artery or capillary individually. We have to put them all together to see that the total area of the capillaries is 100 times larger than that of the arteries or veins. Blood flowing through arteries or veins is going faster because there is less area.
Blood velocity is inversely proportional to each of the areas of its territories. The greater the area, the lower the speed.
