Answer:
Volume of the sample: approximately
.
Average density of the sample: approximately
.
Assumption:
.
.- Volume of the cord is negligible.
Explanation:
<h3>Total volume of the sample</h3>
The size of the buoyant force is equal to
.
That's also equal to the weight (weight,
) of water that the object displaces. To find the mass of water displaced from its weight, divide weight with
.
.
Assume that the density of water is
. To the volume of water displaced from its mass, divide mass with density
.
.
Assume that the volume of the cord is negligible. Since the sample is fully-immersed in water, its volume should be the same as the volume of water it displaces.
.
<h3>Average Density of the sample</h3>
Average density is equal to mass over volume.
To find the mass of the sample from its weight, divide with
.
.
The volume of the sample is found in the previous part.
Divide mass with volume to find the average density.
.
<h2>The acceleration of car is 0.2 ms⁻²</h2>
Explanation:
When the car moves , the distance covered is calculated by the relation
S = u t +
a t²
In this question u = 0 , because car was at rest initially
Thus S =
a t²
here S is displacement and a is the acceleration of car
Therefore 360 =
a ( 60 )²
Because time taken is one minute or 60 seconds
Therefore a = 
or a = 0.2 m s⁻²
Answer:
4. It is the force of the road on the tires (an external force) that stops the car.
Explanation:
If there is no friction between the road and the tires, the car won't stop.
You can see this, for example, when there is ice on the road. You can still apply the brakes (internal force), but since there is no friction (external force) the car won't stop.
The force of the brakes on the wheels is not what makes the car stop, it is the friction of the road against still tires that makes it stop.
Answer:
new atmospheric pressure is 0.9838 ×
Pa
Explanation:
given data
height = 21.6 mm = 0.0216 m
Normal atmospheric pressure = 1.013 ✕ 10^5 Pa
density of mercury = 13.6 g/cm³
to find out
atmospheric pressure
solution
we find first height of mercury when normal pressure that is
pressure p = ρ×g×h
put here value
1.013 ×
= 13.6 × 10³ × 9.81 × h
h = 0.759 m
so change in height Δh = 0.759 - 0.0216
new height H = 0.7374 m
so new pressure = ρ×g×H
put here value
new pressure = 13.6 × 10³ × 9.81 × 0.7374
atmospheric pressure = 98380.9584
so new atmospheric pressure is 0.9838 ×
Pa