A physics book slides off a table at 1.25ms and hits the ground after 0.4s

A cart on an air track is moving at 0.5m/s when the air issuddenly turned off. THe cart comes to rest in 1m. The experimentis re

Licemer1 [7]

Answer:

D = 4 m

Explanation:

Speed of cart in air track v₁ = 0.5 m/s

Speed of cart moved when air is turned off v₂= 1 m/s

The distance travelled by the cart is d₁ = 1 m

Work done (W) = F x d

Work done is equal to the kinetic energy

F x d = 1/2mv²

velocity is directly proportional to distance

therefore,

v₁²/ v₂² = d₁ / d₂

d₂ = d₁v₂² / v₁²

= 1 m x (1 m /s)² / (0.5 m/s)²

= 4 m

5 0

3 years ago

Suppose that a solid ball, a solid disk, and a hoop all have the same mass and the same radius. Each object is set rolling witho

8090 [49]

Answer:

Hoop will reach the maximum height

Explanation:

let the mass and radius of solid ball, solid disk and hoop be m and r (all have same radius and mass)

They all are rolled with similar initial speed v

by the law of conservation of energy we can write

$K_{trans}+K_{rot}= P$

for solid ball

$[tex]\frac{1}{2}mv^2+\frac{1}{2}I_{ball}\omega^2= mgh_{ball}$

putting $I_{ball}=\frac{2}{5}mr^2 and \omega=\frac{v}{r}$ in the above equation and solving we get

$h_{ball}= 0.071v^2$

now for solid disk

$[tex]\frac{1}{2}mv^2+\frac{1}{2}I_{disk}\omega^2= mgh_{disk}$

putting $I_{ball}=\frac{1}{2}mr^2 and \omega=\frac{v}{r}$ in the above equation and solving we get

$h_{disk}= 0.076v^2$

for hoop

$[tex]\frac{1}{2}mv^2+\frac{1}{2}I_{hoop}\omega^2= mgh_{hoop}$

putting $I_{hoop}=mr^2 and \omega=\frac{v}{r}$ in the above equation and solving we get

$h_{hook}= 0.10v^2$

clearly from the above calculation we can say that the Hoop will reach the maximum height

5 0

3 years ago

Doubling an objects speed will have what effect on its potential energy due to gravity

prohojiy [21]

An object's gravitational potential energy is

(mass) x (gravity) x (height above ground) .

I don't see the object's speed anywhere in that formula, do you ?

An object's speed has no effect whatsoever on its potential energy ... only if it changes the object's height above ground.

4 0

3 years ago

Two movers use a rope system to lift a box to a third-story apartment. They do 1,200 J of work on the rope system, and the rope

xeze [42]

Efficiency is defined as the measure of the amount of work or energy is conserved in a certain process. At all times, in every process, work or energy is always lost or wasted due to certain interference. Not all work given is converted to useful work or energy. Thus , efficiency is calculated by dividing the energy or work output to the energy or work input then the value is multiplied by 100 to express efficiency as percentage.

Efficiency = work output / work input
Efficiency = (1020 J / 1200 J) = 85%

8 0

3 years ago

Read 2 more answers

Set kinetic energy equal to potential energy and solve for velocity

nikdorinn [45]

KE = PE
1/2 m • v^2 = mgh
1/2 • v^2 = gh
V^2/2 = gh
2 • (v^2/2) = 2 • (gh)
V^2 = 2gh
V = sq root (2gh).

8 0

3 years ago