# RE: phhysics

Posted by Charlene on Friday, March 23, 2007 at 3:00am.

picture in your mind a block that slides without friction down a ramp that is inclined at an angle (q) above the horizontal. Initially the block is at rest a distance (s) in meters (measured along the plane) from the bottom. Calculate the time (in seconds) required for the block to slide to the bottom.

can some1 show me the formula to find the time? for some reason, i can't find it in my textbook.

* physics - drwls, Friday, March 23, 2007 at 8:04am

With no friction, the weight component down the ramp is Mg sin A, where g is the angle. That equals M a, so the acceleration is a = g sin A
The time T required is given by
(1/2)a T^2 = (1/2)g sin A
Solve for T

ookk. but what if there is no weight or mass of the block given? and only the angle and length? which is: 1 degrees & 300 meters. i have to find T in seconds.. would i do this?

(1/2)a T^2 = (1/2)g sin A
(1/2)(-.999)(T^2) = (1/2)(1)sin(300)

?? im still confused. help!

Please note the mass divides out, you don't need it.

a= gSinA
s= 1/2 a t^2 put in a, then solve for t.

t= sqrt 2s/a = sqrt (2s/gSinA)

thanks!

.. i kept gettin' the wrong answers.. and i was doing everything correctly!! then i realized my calculator was set to radians instead of degrees. arggh! lol

1. 👍
2. 👎
3. 👁

## Similar Questions

1. ### physics

A 3 kg block (block A) is released from rest at the top of a 20 m long frictionless ramp that is 5 m high. At the same time, an identical block (block B) is released next to the ramp so that it drops straight down the same 5 m.

2. ### Gr10 Math

Charlene is looking into cell phone plans. Cell plus gives unlimited minutes for \$50/month.A1 Cell offers a \$40 monthly fee, plus 5¢/min for any time over 300min oer month. a)Define two variables and write a linear equation to

3. ### English

Identify the sentence that uses the present perfect progressive tense correctly. A. Charlene is feeling sick today. B. Charlene was sick. C. Charlene has been feeling sick lately. D. Charlene feels sick. C

4. ### physics

3 kg block (block A) is released from rest at the top of a 20 m long frictionless ramp that is 5 m high. At the same time, an identical block (block B) is released next to the ramp so that it drops straight down the same 5 m. Find

1. ### Physics

What is the acceleration of the upper block? The coefficient of kinetic friction between the lower block and upper block is 0.0005. The coefficient of kinetic friction between lower block and floor is 0.0001. Upper block is 1kg,

2. ### Physics - drwls

Posted by winterWX on Monday, March 19, 2007 at 11:51pm. A 2600 kg truck traveling north at 38 km/hr turns east and accelerates to 55 km/hr. What is the change in the truck's kinetic energy? What is the magnitude of the change in

3. ### Social studies

What is the longitude of Cairo whose time is 10:00am when the time of accra is 8:00am the same day

4. ### Probability

Given the probability of rain on any given day in March is 1/5, find the probablity that: It rains on March 10 and 12, but not on March 11th. This is supposed to be used with multiplication Rule 1: P(A and B)= P(A)*P(B) cant

1. ### physics

A string going over a massless frictionless pulley connects two blocks of masses 4.4 kg and 11 kg. As shown on the picture below, the 4.4 kg block lies on a 23◦ incline; the coefficient of kinetic friction between the block and