All categories

3 years ago

3. What average net force is required to stop a 7 kg shopping cart in 2 s if it's initially

Physics

1 answer:

stiv31 [10]3 years ago

8 0

-12.25N

Explanation:

Given parameters:

Mass of shopping cart = 7kg

Time = 2s

initial velocity = 3.5m/s

Unknown:

Average net force required to stop the cart = ?

Solution;

According to newton's second law"acceleration of body results when a net force acts on a body".

F = ma

where F is the force

m is the mass

a is the acceleration

Acceleration is the change in velocity with time

a = $\frac{v - u}{t}$

Therefore;

F = m x $\frac{v - u}{t}$

v is the final velocity, in this case it is zero, 0

u is the initial velocity

t is the time taken

Putting in the parameters:

F = 7 x $\frac{0- 3.5}{2}$ = -12.25N

This force that will stop the cart will be directed in the opposite direction with a magnitude of 12.25N

Learn more:

Newton's law brainly.com/question/11411375

#learnwithBrainly

You might be interested in

In pairs figure-skating competition, a 65-kg man and his 45-kg female partner stand facing each other both at rest on the ice. I

Lina20 [59]

Answer:

The final velocity of her partner is approximately -1.04 m/s or 1.04 m/s in the opposite direction to her direction of motion

Explanation:

The given parameters are;

The mass of the man, m₁ = 65 kg

The mass of the woman, m₂ = 45 kg

Taking the relative initial velocity of the man and the woman as 0 m/s, we have;

The initial velocity of the man, v₁₁ = 0 m/s

The initial velocity of the man, v₁₂ = 0 m/s

The final velocity of the woman, v₂₂ = 1.5 m/s

The final velocity of the man = v₂₁

Therefore, we have, by the conservation of momentum principle;

The total initial momentum = The total final momentum

Which gives;

m₁ × v₁₁ + m₂ × v₁₂ = m₁ × v₂₁ + m₂ × v₂₂

Substituting the known values;

65 × 0 + 45 × 0 = 65 × v₂₁ + 45 × 1.5

∴ 65 × v₂₁ + 45 × 1.5 = 0

45 × 1.5 = - 65 × v₂₁

v₂₁ = 45 × 1.5/(-65) ≈ -1.04 m/s

The final velocity of the man, her partner = v₂₁ ≈ -1.04 m/s.

6 0

3 years ago

A tow truck drags a stalled car along a road. The chain makes an angle of 30???? with the road and the tension in the chain is 1

My name is Ann [436]

Answer: work = 1,305kJ

Explanation:

angle= 30°

force= 1,500N

distance= 1,000m

The formula for work is : Work= force x distance, however there is an angle of 30° between the direction of force applied and the direction of motion, therefore force must be decomposed to its value on the horizontal axis which is the direction of motion by using the cosine of the very angle.

W= F×cos(α)×D

W= 1,500×cos (30)×1,000

W= 1,305kJ ( kilojoules)

3 0

3 years ago

What is the equation for force

Basile [38]

The equation is F=ma :)

3 0

3 years ago

Read 2 more answers

what is the resistance of a clock if it has a current of 0.30 a and runs on a 9.0-v battery? 0.033 2.7 9.3 30

Nataliya [291]

R = V/I = 9 / 0.3

R = 30 ohms.

5 0

3 years ago

Read 2 more answers

In a certain time interval, natural gas with energy content of 19000 J was piped into a house during a winter day. In the same t

Bumek [7]

Explanation:

Since, it is mentioned the there occurs no change in the temperature. This also means that there will occur no change in thermal energy of the system.

Hence, $\Delta E$ = 0. And, as $\Delta E$ = 0 then there will be no work involved. This means that total energy added to the house will return to the outside air as heat.

Therefore,

Q = -(19000 J + 2000 J)

= -21000 J

or, |Q| = 21000 J

Thus, we can conclude that the magnitude of the energy transfer between the house and the outside air is 21000 J.

5 0

3 years ago