All categories

3 years ago

What is a Lever?

2 answers:

8 0

Lever: a bar used to move something
Wedge: a tool used to go in between object to put them in place
Incline plane : a ramp it’s used to help rise heavy things
Pulley: it’s a wheel that supports movement and change of direction

Mariulka [41]3 years ago

4 0

Answer:lever

Explanation:

You might be interested in

The average 8- to 18-year-old spends __________ per day on average in front of a screen doing very little to no physical activit

natta225 [31]

Answer:

D. 3 hours or more

Explanation:

The average 8- to 18-year-old spends at least D. 3 hours every day in front of a screen, performing little to no physical activity. This is because, instead of exercising and socializing with their peers, children and teenagers frequently talk, watch a lot of movies/shows, or play video games on their computers. Unfortunately, this is typically considerably more than three hours every day. Although some children still prefer physical activities over this, the bulk of the population does not.

5 0

2 years ago

Car B has the same mass as Car A but is going twice as fast. If the same constant force brings both cars to a stop, how far will

evablogger [386]

Answer:four times

Explanation:

Given

mass of both cars A and B are same suppose m

but velocity of car B is same as of car A

Suppose velocity of car A is u

Velocity of car B is 2 u

A constant force is applied on both the cars such that they come to rest by travelling certain distance

using to find the distance traveled

where, v=final velocity

u=initial velocity

a=acceleration(offered by force)

s=displacement

final velocity is zero

For car A

$0-(u)^2=2\times a\times s$

$s_a=\frac{u^2}{2a}------1$

For car B

$0-(2u)^2=2\times a\times s_b$

$s_b=\frac{4u^2}{2a}----2$

divide 1 and 2 we get

$\frac{s_a}{s_b}=\frac{1}{4}$

thus $s_b=4\cdot s_a$

distance traveled by car B is four time of car A

7 0

3 years ago

The acceleration due to gravity on the surface of Mars is gmars = 3.7 m/s2. How much would an 11 kg bag of potatoes weigh on Mar

allsm [11]

Fnet = (mass) (acceleration)
= 11 kg x 3.7m/s^2
= 41 N

6 0

3 years ago

A passenger in a helicopter traveling upwards at 15 m/s accidentally drops a package out the window. If it takes 15 seconds to r

Alexeev081 [22]

Answer:

The helicopter was 1103.63 meters high when the package was dropped.

Explanation:

We consider positive speed as a downward movement

y: height (m)

t: time (s)

v₀: initial speed (m/s)

Δy = v₀t + $\frac{1}{2}$ gt²

Δy= 15 $\frac{m}{s}$ ×15 s + $\frac{1}{2}$ ×9.81 $\frac{m}{s^{2} }$ ×(15 s)²

Δy= 1103.63 m

8 0

3 years ago

A driver with a 0.80-s reaction time applies the brakes, causing the car to have acceleration opposite the direction of motion.

jeka94

Answer:

a) During the reaction time, the car travels 21 m

b) After applying the brake, the car travels 48 m before coming to stop

Explanation:

The equation for the position of a straight movement with variable speed is as follows:

x = x0 + v0 t + 1/2 a t²

where

x: position at time t

v0: initial speed

a: acceleration

t: time

When the speed is constant (as before applying the brake), the equation would be:

x = x0 + v t

a)Before applying the brake, the car travels at constant speed. In 0.80 s the car will travel:

x = 0m + 26 m/s * 0.80 s = <u>21 m </u>

b) After applying the brake, the car has an acceleration of -7.0 m/s². Using the equation for velocity, we can calculate how much time it takes the car to stop (v = 0):

v = v0 + a* t

0 = 26 m/s + (-7.0 m/s²) * t

-26 m/s / - 7.0 m/s² = t

t = 3.7 s

With this time, we can calculate how far the car traveled during the deacceleration.

x = x0 +v0 t + 1/2 a t²

x = 0m + 26 m/s * 3.7 s - 1/2 * 7.0m/s² * (3.7 s)² = <u>48 m</u>

4 0

3 years ago